Monday 18 January 2021

American Football - an introduction

 In my college days, when India had only one television channel, Doordarshan, which was owned and operated by the Indian Government, there was a news program called “The world this week” produced by a private company, which today is NDTV, a private 24 hour news channel. Every year they would show a minute of highlights from an American football game, which for some unfathomable reason was called Superbowl. Like most of the world I only knew soccer football then. This American football seemed very strange, with a ball shaped like a rugby ball, which was also an alien game – but why call it football when all you seem to do is throw it and someone else is catching it. Just to add to the confusion, there were also a couple of instances when somebody kicked the ball through upside down goal posts. All the players seemed like heavyweight boxers, wore huge padded suits that made them look like Batman without his cape or mask. Occassionaly, I saw American football in movie clips and in comic books like Archie and Superman; once, in a Mandrake comic book.

American football in an Archie comic book
Picture from The Deep Friar blog

Nothing like my beloved cricket. Not even as watchable as tennis or car racing. I was no big fan of soccer, though I watched a few World Cup games. But a weird mysterious curious bizarre game, seemed this American football.

College Football

And then a few years later I went to the USA, to study. As it happened, I landed up in a football crazy state, Texas – while America seems uniform to outsiders, each state has its own character, that foreigners only slowly comprehend after years of stay. Some Texans joke that Texas has two religions, Christianity and football, not necessarily in that order. And that is saying something, as Texas is in the heart of the Bible belt. (Cricket has acquired a similar status in India, hasn’t it?)

I entered into a Master’s program in Computer science at a university with a good college football team, Texas A&M University (TAMU). College sports are a huge money spinner, and cultural focus of identity for most universities in the USA. The autumn or fall semester, September to December is also college football season: all American sports are seasonal. And every Saturday afternoon my roommates and a couple of neighbors, all students from India, mostly from Madras, in TAMU for graduate studies, gathered to watch TAMU play football on TV. In a few weeks, I started watching professional football, which was played on Sundays, and also shown on TV. It took me a few weeks to understand the basic rules – every sport is much easier to understand if you actually play it, not merely watch it on TV; and football while extremely popular on American TV, is rarely played on its streets or grounds, except by formal teams in schools and colleges. This is very much unlike basketball or baseball or even soccer or volleyball. The sport most similar in this stark contrast, is car racing.

College football
Texas A&M University vs North Carolina University


While I enjoyed the college version, especially because it is very easy to root for the TAMU college team, the professional sport was not only superior, it was better presented. In India, the only team I ever rooted for in the 1980s and 1990s was the national team – there was no professional leauge. The amateur league, where teams were divided by state, which played for the Ranji Tropy, was never on TV, and unwatchable unless you were a desperate fanatic, and a Bombay fan. Technically all Indian sports team comprised of amateur athletes, because they were all nominally employees of some company or the other like a bank, Railways, Telephones etc. all owned by either the central or state governments.

Professional Sports

Socialist dullness pervaded every sport except cricket from my perspective. The only professional athletes in India were in ancient Indian sports like wrestling or bull fighting or bullock cart racing, most of which urban democratic India was ashamed of and tried to suppress or destroy in various ways. As a modern city slicker they were beneath even my contempt anyway. They were never shown on Doordarshan (government run television), but very popular in cinema, which was in the hands of private entreprise. But cinemas showcased these sports so poorly, only the country hicks enjoyed them in real life. (I had to go to college for four years in a rural setting, before fully understanding how cut off we city slickers were from half of India, and how arrogant and ignorant and condescending we are.)

I had no idea how loyalties worked in professional sports in America, not just in football but also in Baseball and Basketball, the two other extremely popular sports. The teams were all based on cities not states. The Chicago (city) Bears, not the Illinois (state) Bears. The Dallas (city) Cowboys not the Texas (state) Cowboys. Exceptions were Minnesota and Arizona where the teams were named for their states, and New England named for an area with multiple states. The players came from all over the USA, usually having played for some college team. The colleges themselves had a caste or class system, with about 100 Universities called First Division, forming a pool from which the players for the professional leagues were chosen.

In 1991, I didn’t have  favorite team, though my friends and roommates liked the Houston Oilers, Houston being the nearest city. When the 1992 season started, after a few weeks I realized I like the Dallas Cowboys more than the Oilers. Dallas was a better team. That unit turned out to one of the best in NFL history.

There were several small professional leagues in American football, but the biggest, richest league and most visible on TV, was the National Football League. There used to be another league called the American Football League, but the two merged in 1960, and became two subunits of the same league. They just called themselves National Football Conference and American Football Conference. There were fifteen teams in each group divided into three divisions, but now there are sixteen teams divided into four divisions, called North, South, East and West. The teams with best records after the sixteen games in each division, play two others with the best records in some playoffs within each conference. The winner of both conference playoffs face off in the Superbowl, the most watched TV program every year in the USA.

I stopped watching the NFL after I returned to India, mainly because those games happen at what is nighttime in India. But in 2015, I saw some ten minute highlight clips of Sunday games and watched a few (sometimes on the laptop, sometimes on my smartphone after 3G or 4G delivered high quality videos). Since then I have been hooked again, watching these highlights every Monday morning. The full game is fun to watch if you have friends watching with you, but the ten to twelve minute clips are well mostly well edited, the comments are sometimes terrific, and some post game chats are also delightful.

How it is played

Let me give an illustrated guide to the game. I doubt anyone will start following the game, based on this essay, but, what the heck. One more arrow from quiver of Quixotism, after equally quixotic introductions to Carnatic music, Indian astronomy, Pallava grantham script, temple architecture, etc.

There are three aspects to the game – running the football, passing the football and yes, also, kicking the football. Americans spell English words differently, eat with forks in their right hands instead of the left, modified cricket to turn it into baseball, use a different elecric voltage and system of plugs compared to the English world, drive on the left side of the roads - and they play football in a way the rest of the world doesn’t even bother to pay attention. After 150 years of trying to be less English than the English, they decided it was more important to be less European than the rest of Europe, after the two world wars. Anyway…

The football field is a 100 yards long (the one English thing America continues is their imperial measurement system) and 160 feet (about 50 yards) wide. Every five yards is marked with a full painted line from one side to the other, and every one yard is marked off with a hash mark, two on the sidelines, two in the center a few yards apart. The ten yard lines are marked 10,20, 30, 40 on each side, with the centerfield marked 50. On each end of the 100 yards is a 10 yard long region called the endzone. The game starts with a kickoff, determined by coin toss. The football is placed on a small plastic tee at the 35 yard line of the kicking team’s side. A kicker kicks it off, and tries to land it between the end zone and the 20 yard line of the opposite team. One player of the receiving team will try to catch the kicked ball and run it all the way the end zone of the other team. He is usually stopped tackling after a few yards by the one or more players of the kicking team, by physically tackling him. The receiving team (called the offense) starts its possession (like an inning), and tries to move the ball by passing or running the ball until it reaches the opponent’s endzone. If a running player (usually called the Running Back) enters the endzone with the ball, or passing player (usually called the QuarterBack) throws the ball to a Receiver.

A possession consists of a series of plays. The ball is placed on the ground at the hashmark where the previous play ended. This is called the line of scrimmage, for each play. If the receiver or runner of the offense was tackled at their 24th yard line, the ball is placed on the 24th yard line.

The offense has to assemble in a formation – five players called Offensive Linemen will line up, at the Line of Scrimmage. The central player called Center, will hold the ball on the ground, then snap it backwards between his legs to the Quarterback. Two offensive players line up at the two ends of the line. These are usually the designated Wide Receivers. Four players including the quarterback, form the backfield. Usually the other players are Running Backs. Each play begins when the Center snaps the ball to the Quarterback, who can choose to either pass (throw) the ball to one of the Wide Receivers or hand it off to one of the Running Backs, who will then try to carry the ball (run) towards the Defensive side.


In yellow rectangle - Offensive Line (Buffalo Bills, red uniform);
In blue rectangle - Defensive Line (Pittsburgh Steelers, white and yellow uniform)

Offense Formation
Top view



The eleven players of the Defense also have a basic formation, usually four players called the Defensive Line facing the Offensive Line with a one yard neutral zone between them. Behind the Defensive Line are three LineBackers. When the ball is snapped, the four players of the Defensive Line charge at the five players of the Offensive Line, and try to get past them to tackle whoever is holding the ball (Quarterback or RunningBack). The LineBackers have the option of either charging along with Defensive Line or dropping back to stop the Running Back, if he manages to break through to the other side.

Also on the defense, two CornerBacks line up facing the two Wide Receivers at either end of the Offensive Line. Their job is to prevent the WRs from catching the ball. They may not hold them, grab them or tackle them before they receive the ball thrown by the Quarterback, but may try to catch the ball themselves or hit the receiver as he catches it to stop him at that point or force an incomplete pass. If a player drops a catch or catches it outside the sidelines or even with one of his two feet outside the sideline, it is considered incomplete. The Wide Receivers or the Running Back try to reach the opponents EndZone – if they cross the line with the ball or catch it in the ten yard wide EndZone, it is called a Touchdown and the offense gets six points.

Quarterback hands over ball to Running Back 

Quarterback throws ball to Wide Receiver


Just in case an offensive runner or receiver manages to get past the Linebackers or Corner Backs, there are two more defensive players called Free Safety and Strong Safety who twenty to thirty yards behind the defensive line to try and tackle them. The play ends when the runner or receiver is either tackled to the ground or goes out of bounds (goes beyond either sideline). The line where they are tackled is now the new line of scrimmage, and a fresh play starts with both teams lining up in formation, a fresh snap by the Center. If a ball is dropped (incomplete pass), the next play starts at the same line of scrimmage.

The first line of scrimmage of each possession is called First Down. The offense is allowed four Downs, called obviously First Down, Second Down, Third Down and Fourth Down to move the ball ten yards from the first line of scrimmage. If they manage it or go even farther (say fifteen or nineteen or twenty six yards), they get  a new First Down. Each offensive possession is a series of small First Down attempts, to eventually reach the End Zone and score a touchdown. There are no point for any of the downs.

If after the third down, the offense hasn’t managed to move the ball ten yards forward from the First Down line, they can choose to punt the ball, or try one more pass or run. In a punt, the center snaps the ball to a punter, who is usually about fifteen yards behind the line of scrimmage (not one foot behind, like the Quarterback). He catches the ball with his hands and tries to drop kick it as far as he can to the other side, from which point the other team starts their possession and series of First Downs.

Usually the offense punts if they are at least forty yards or more away from the endzone. If they are within the forty yard line of the opponents side, though, they may instead try a field goal. This is where the Center snaps a ball to a Holder, who is kneeling about seven yards behind him, places it on the ground and a Kicker tries to kick the ball between the upright goal posts. If he succeeds, the team gets a Field Goal, which is worth three points (half the six point of a Touchdown). If he misses (that is, the ball drops short or goes left or right of the goal posts), the defense starts their possession from the line of scrimmage. That is why the offense doesn’t try to usually kick very long field goals (remember the field goal has to go ten yards longer than the touchdown).



A long field goal attempt - from 54 yards away

If the offense scores a Touchdown, they are allowed to make an extra point attempt. They can either try to kick the ball from the ten yard line for one extra point, or try to run or pass into the endzone again from the two yard line for two extra points. So a touchdown is worth more than just two field goals.

LasVegas Raiders Wide Receiver (in black and white uniform)
heads into the endzone (painted black) having beaten Indianapolis Colts defenders (white and blue)

Referee signals a Touchdown, by raising both hands

This is a just briefing of a small set of rules of American football (I have said nothing about penalties for example, and special exemptions). It usually takes the newbie to the sport several weeks or months of watching the game before picking up the basic elements. And this is why the game is not popular outside the USA (Canada plays its own version with slightly different rules), except among people who have spent a few months in the USA. Hence basketball and baseball are more  popular US cultural exports. The rules for cricket are just as complex, which is why only former colonies of England play that game.

The degree of specialization is somewhat insane. Each team actually has separate teams for Offense, Defense and Kicking (called Special teams). That means a minimum roster of thirty three (three sets of eleven). A full team roster usually has nearly fifty players. Even the punter and field goal kicker are two different players. The Quarterback almost never plays any other position, for example, though he sometimes runs the ball, if none of his wide receivers is open and free to catch the ball. The Offensive Line may not catch or run the ball, they may only block the defense. 

The head coach of each team is highly critical, in a way peculiar to American sports (basketball and football head coaches also have enoromous say in almost every play). The coaching staff for each team runs into double digits. The money is quite astounding. Outside the USA, only soccer players and Formula 1 drivers make comparable amounts of money (boxers too, but they are usually American).

Head coaches of several university football teams (which are amateur sports – no college player is paid) are paid a million dollars – some of them are paid more than the President (ViceChancellor) of their University or Governor of their State.

Strategies and Trick plays

What makes America football fun, is not just the basic rules and games, but the strategies, trick plays, ununsual formations, and incredible athleticism, that is often on display.

A common example of athleticism is when a Running back tries to leap over the defensive line, into the endzone, to score a touchdown. (Cricket metaphor: Like a batsman diving over the crease to avoid a run out, or a fielder diving for a catch).



Deception is often the best form of offense. The most common trick play is called play-action. In this, the Quarterback pretends to hand over the ball to Running back, but doesn’t. The Running back pretends to tuck the ball and run forward. The Linebackers of the defense therefore, assume that it is a run attempt, rather than a pass attempt, and try to block the runner from coming through one of the gaps between the players of the Offensive Line. They are only fooled for about two seconds, but these two seconds is what the Quarterback needs to drop back without being rushed and in these two seconds, one or more of the Wide Receivers may get a two yard separation from the Cornerback covering him. The Quarterback then passes it to whichever WideReceiver is open. As soon as the ball is thrown, the entire defense can see who is the intended receiver and the nearest players try to tackle him. (Cricket metaphor : Spinner’s googly or batsman’s reverse sweep).

Another trick play is when the Quarterback passes the ball backward to a Wide Receiver or Running Back. The catcher may only be a yard behind the horizontal line on which the QB stands, and the defense will assume he is trying to run after the catch, and will tackle him. But the catcher now throws the ball to an open Wide Receiver, whose defenders are momentarily distracted and gets far more yards than the first pass and run would have fetched.

Trick play part 1 - QB passes backwards to RB
Cornerbacks allow Wide receivers past them, go to tackle RB

Trick play part 2
RB passes to WR, who is now 15 yards past cornerbacks 

There are a vast number of trick plays with fascinating names like Statue of Liberty play, fake punts (whether the special team lines up for a punt, but the punter throws the ball to a wide receiver for a first down), fake field goal, reverse (a wide receiver comes around to take the quarterback’s handoff rather than the running back), flea flicker, shovel pass, and so on. They are spectacular when they come off, and seem silly when they dont.

Here is another strange play, perhaps not originally planned as such, where QuarterBack Patrick Mahomes of Kansas City, (No. 15, in white and red uniform) escapes a tackle, runs toward the first down, but shovels a backwards pass underhanded to a Running Back behind him. Mahomes is the Virat Kohli or Steve Smith of football, the most exciting new player since Tom Brady. He led his team to a SuperBowl victory last year and may do so again this year.

Backward pass from Patrick Mahomes (No. 15) to Running back
Notice Line of scrimmage in blue
Receivers are blocking defenders downfield of Mahomes


But the defense is also made of intelligent human beings, and they often detect the offense’ tricks and try to spoil it. One such play is when a cornerback guesses the intended receiver and jumps in front to catch the ball. This is called an interception, and if Cornerback catches it, the defensive team now gets possession, from the spot where it was intercepted. The intercepting player can also run the ball towards his opponents endzone, and if he reaches it, the he scores a touchdown and gets six points. If he manages to only run a few yards before he is tackled by one of his opponents, that becomes the starting line for the intercepting team

Cornerback (No 23 in white uniform) leaps to intercept
 ball intended for Wide Receiver (No. 83 black and silver uniform) 

An interception is one of three possible turnovers. Another is when a running player drops the ball or the ball is slapped out of his hands, before his back or knee hits the ground. This is called a fumble. If the fumble is recovered by his own teammate, they continue from there, but if one of the defensive players grabs it, he can return it to the opponents end zone or as far as he can.

Sometimes, the offense is barely one yard or one foot short of the first down marker, and will go for a run or pass on fourth down. If they don’t make it, the opponent starts possession at the point they stopped the offense. This is called a Turnover on Downs. Usually the offense only tries this when they are well into the opponents territory and they want to score a touchdown rather than settle for a field goal.

Remember Offensive Line has five players and the Defensive Line usually has only four, with three Linebackers hanging back. Sometimes two of these linebackers try to cut through the offensive line, with a six on five mismatch. This is called a Blitz. Then they try to tackle the Quarterback before he can pass or the Running back while he is still behind the line of scrimmage. This is called a Sack. Say the offense is on their own 24th yard line, First Down and 10 yards to go. They have to reach the 34th yard line for fresh First Down. If one of the blitzers tackles the ball carrier at the 20 yard line, the offense now has Second Down and 14 yards to go.

Sometimes a cornerback or safety comes around the end of the offensive line for a blitz, rather than a linebacker trying to cut through. A lot of the strategy in football is the offensive line blocking the defense in creative ways, and the defensive line trying to cut through the offensive in equally ingenious ways. TV commentators rarely highlight this, but it is where half the games are lost or won, away from the ball. The players on the offensive and defensive line invariably weigh more than three hundred pounds (140 kg) and are built for almost wrestling skill, not speed and mobility.

Excellent blocking 
Offensive Line (black uniform) protects QB (left extreme)
from defense (white uniforms), giving him time to throw

QB (left extreme) on 30 yard line
throws the ball just avoiding the blitz

SanFrancisco QB in (red and gold uniform)
sacked by Dallas Cowboys cornerback (white uniform) who broke through the Offensive Line


Quarterback Tom Brady (12) gets past defensive line 
avoiding the blitz

This last picture of Quarterback Tom Brady of the Tampa Bay Buccaneers, avoiding the sack, is interesting. While the offensive and defensive linemen are locked in blocking, he has managed to get past them and is about to throw to a Wide Receiver (right extreme), who is just past the first down marker (yellow line - graphics effect). The Line of scrimmage for this play is the blue line (graphics effect. 

Tom Brady is the Donald Bradman of the American football. He has reached nine Superbowls, playing for the New England Patriots, and won six in a twenty year career. Some excellent football players have never reached the Superbowl, and only a few have even reached four Superbowls. In early 2020, the Patriots released him and he joined the Tampa Bay team, which won its first playoff in thirteen years, under him, and today (Sunday Jan 17, 2021) he won another playoff game against the New Orleans Saints.

But I have already perhaps written more about football than any reader of my blog is likely to read or understand. So I will stop, here.

Most of the pictures were taken from screen captures of Youtube videos of these NFL games. The Archie comic picture is from The Deep Friar blog 

Related blogs

On cricket – The Sehwag difference

The art and aesthetic of driving cars(Formula 1)

A Texas table tennis story

An Introduction to Carnatic music

Indian Mathematics and Astronomy course

Pallava Grantham classes

Sunday 3 January 2021

A brief timeline of Vaccinations

I am neither a doctor, nor biologist, nor historian. I first studied this for a lecture about Vaccination in Madras, for the Madras Local History Group. I have merely provided some dates and data, for an easier read.

Ignaz Semmelweiss


Before Sterilization and Germ theory

  • 1700s Lady Montague inoculates her children in Turkey, introduces vaccination to England
  •     English aristocrats inoculate their children
  • 1794 Edward Jenner starts variolation and vaccination
  • 1858 Great Stink of London, Thames cleaning begins
  •     Darwin-Wallace paper on Evolution presented by Lyell and Hooker
  •     Five of Darwin's children died in infancy (did vaccination not save them?)
  • 1864 Louis Pasteur discovers Germs cause diseases
  •     Antibodies, white blood cells discovered
  • 1847 Ignaz Semmelweiss discovers importance of sterilization, in Austria
  • 1848-1860 Political Turmoil in Europe
  • 1861 Semmelweiss campaigns for doctors to wash hands between surgeries
  •     Doctors refuse to wash hands, blood stains seen as symbols of valour
  • 1865 Semmelweiss sentenced and imprisoned in a lunatic asylum, for his sterilization campaign; dies 

After discovery of Sterilization

  • 1865 Lister advises Wash hands, use gloves, introduces anti-septics
  • 1860 John Snow discovers feces infested water causes cholera, campaigns for clean water. 
  •     John Snow: "Boil water before drinking"
  • 1861 Death by typhoid of Prince Albert, husband of Queen Victoria
  •     Campaign to clean up River Thames, London, build sewerage system
  • 1861 Europeanization of toilets, sewers.
  •     Globalization takes another century

Vaccination Laws in England

  •     1840 Free Vaccination
  •     1855 Compulsory Vaccination
  •     1867 Penalty to resist Vaccination

  • 1870 Robert Hooker: "Wallace has lost caste" (because Wallace explored spirituality, seances. Wallace also doubts that human mind evolved by Natural Selection)
  • 1890 Robert Koch : Different germs cause different diseases
  • 1896 Alfred Russel Wallace publishes book "Vaccination a Delusion, its penal enforcement a crime"
(This book by Wallace is out of print. A free version is available on Kindle, but very badly formatted)

I now suspend the timeline for some notes from Wallace's book

Wallace findings

  • Jenner: Less than 2000 deaths upto 1800
  • Parliament 1836: 5000 deaths before 1800
  • Dr Ernest Hart British Medical Journal 1880: 18,000 deaths per million
  • National Vaccination Society 1884: Before vaccination, 40,000 dead in England of pox
  • Wallace quip: "Dead were multiplying in the past"

Wallace observations

  • Villages and small towns rarely had deaths. Also far lower death rates than London
  • Filth diseases caused by foul air and water, decaying organic matter, overcrowding
  • Plague and leprosy not eliminated by vaccines but by marginal improvements in hygiene
  • Replaced by cholera, small pox etc as main killers
  • No careful tests were made with two groups one vaccinated, the other not
  • Doctors are bad statisticians
  • Royal Commission had no statisticians, but doctors, lawyers and politicians

Fortunately, unlike Semmelweiss, Wallace was not hounded into a lunatic asylum

(Gopu comment: Cheap cotton textiles, mainly imported from India via several East India Companies, from 1640 onwards, probably played a big role in improving European hygiene. As did the Cotton revolution in England from 1740 onwards.

Also cheaper coal because of James Watt engine made hot water far far cheaper. Average Europeans could bathe in winter almost as often as residents of tropics)

The Timeline continues...

PreModern Era of Medicine

  • 1890 German company Bayer invents Aspirin. Era of chemical medicine, pills, pharmaceutical industry begins
  • Insulin discovered
  • 1930s  Heroin, cocaine, all kinds of snake oil sold over the counter in USA
Modern Era of medicine
  • 1940 Sulfa, Antibiotics make Western medicine better than medicine of other nations for the first time in history (warning: this is only Gopu's opinion) 
  • Rate of decline of death rates go from 2% per year to 8% per year, some of it is credited to vaccines
  • 1945 Transistor invented. Integrated circuits follow soon. Electronic devices make research and medicine far superior in a short time
  • 1954 Polio vaccine invented
  • 1960 Measles mumps rubella (MMR) vaccine invented (Estimate 5000 deaths prevented in 20 years)
  • 1970 Smallpox eradicated
  • 1994 Plague suspected in Surat, Gujarat, India cut off from world for two weeks
  • 2000s Potential epidemics SARS, Ebola, swine flu, bird flu, curtailed before pandemic
  • 2020 January - COVID-19 Coronavirus epidemic in Wuhan, China; parts of Italy, USA; several air travelers
  • 2020 March - Global lockdowns begin
  • 2019 November - Announcements of several COVID-19 vaccines, from UK, USA, Russia, China

Explanatory Note

A small but vocal anti-vaccination movement is active in USA. Wikipedia calls is vaccine hesitancy. But such movements have been common throughout history, not just against vaccination, but against other new forms of medicine or science. Science usually wins, but frequently, what was considered turns out to be very unscientific - examples are : the four humours, phlogistons, phrenology, eugenics, vital forces theory, philosophers stone, Lysenko genetics, and possibly string theory.  Some of these people are extremely unscientific, religious (usually Christian - in the USA), some simply are suspicious of governments and doctors. 

If he were alive today, Alfred Wallace would also be labeled anti-vax and "denier". As his colleague Robert Hooker noted, "Wallace had lost caste."

Make of it what you will

Related Links

On Alfred Russel Wallace    

My essays on Biology 

Darwin's medical problems - and lousy medical treatment

Video of my lecture Vaccination in Madras (for Madras Local History)