Posted by ESPN.com's Tim Griffin
You can't tell your recruits without looking at the color of their shirts.
Recruiting has its own vocabulary describing different players. After popular demand from several readers, here's a quick primer to get you ready for Wednesday's National Signing Day.
Redshirt: The most popular of all recruiting practices. Many freshmen, typically for players wanting an extra year of seasoning for experience and development purposes, will report to a team and do everything with a team except play in its game. The NCAA allows a player five years to complete four years of athletic competition, enabling them to sit out a season to develop for a season. Notable examples are Texas Tech wide receiver Michael Crabtree (sat out 2006 season) and Oklahoma defensive back Lendy Holmes (sat out 2004 season).
Grayshirt: The newest trend in recruiting. A player will sign in a February recruiting class, but will not enroll the following summer with his teammates as a normal scholarship player. Instead, he delays entry until after the season is over, thereby not counting against the team's scholarship total for his original recruiting season. Or, he can attend school for less than nine hours in the fall semester and can work out and learn the team's playbook, but he cannot practice with his team. The chance to redshirt still remains active, essentially giving these recruits six years to play four seasons. Texas Tech is the most active team in this practice, with players like wide receiver Lyle Leong and inside receiver Adam James among their most notable grayshirts. Mike Leach likely will convince others to do this in this year's class.
Greenshirt: A growing trend across Big 12 where players skip their final semester in high school, participating in spring practice at their college coach immediately after their senior season in high school. This practice is most often done by players who are intent on immediately challenging for playing time in their college careers. The earliest player to greenshirt is commonly believed to have been Georgia quarterback Eric Zeier in 1991 and also later included players like Oklahoma quarterback Nate Hybl (also at Georgia). More recently, Texas safety Blake Gideon jump-started his career by coming to college early among others. And top Oklahoma recruits like linebacker Tom Wort and quarterback Drew Allen started school last month as 2009 greenshirts.