Today, American football is arguably the most popular sport in the United States. It is played by people of all ages and on all levels. From youth football to collegiate football to the highly popular National Football League (NFL), the sport has grown into a national obsession. It has even reached other countries, with people in countries such as Japan and Germany getting more and more familiar with American football.

How exactly did the sport come to be? Despite being a sport that was developed and continues to be popular almost entirely in America, American football was actually derived from rugby football. Like rugby, American football is a contact sport in which players mostly catch and carry the ball. This is distinguished from the football played in most other countries in the world (known as soccer in the United States), in which the game is played by kicking the ball around.

One thing that has been disputed in the history of American football is when the first game was played. There are many different games that have laid claim to the title of the first game of American football. However, whichever one was first continues to be disputed because of the differences in rules that each one had and the many differences they have with the American football of today.

Despite the questions about when the first American football game was held, one thing many people agree on is that Walter Camp, a sports writer and football coach from Yale University, is considered the father of American football. He was a football player at Yale University who made many of the most significant modifications and innovations that led to the American football we know today. Many of the characteristics of American football, such as the system of downs, the forward pass, and the number of players, were all formulated by Camp. Without Camp's many contributions to the sport, football in America today might simply be a slightly modified version of rugby, or even a version of the “football” that is played in Europe and the rest of the world.

Linemen are usually the physically largest and strongest players on the field. The physical size of linemen is necessary to protect the backfield players, or to push through the opposing line.

Without a strong offensive line, running lanes cannot be opened for an effective running attack. Likewise, without an offensive line effectively protecting the backfield, the quarterback will not have sufficient time for passing plays to develop downfield. Conversely, without a powerful defensive line to pressure the opposing quarterback, the opposing team can often pass at will without fear of the quarterback being sacked for a loss of yardage.

Offensive linemen are commonly compared to custodians, lunch ladies, and bus drivers. Their work sometimes goes unnoticed and their job is not as popular as the position of teacher, or principal. However, without these wonderful people, teachers and principals couldn't effectively do their job, just as the ever-popular quarterback could never do his job without his offensive line.

There are two types of lineman: offensive linemen and defensive linemen. The offensive linemen comprise the offensive line, while the defensive linemen comprise the defensive line. When an offensive lineman and a defensive lineman are compared to each other, the offensive lineman is usually the larger, stronger. The defensive lineman is the faster, more athletic.