[Editor's Note: The following is a small piece of college football preview section available in Sunday's Atlanta Journal-Constitution.]

College football fans, who long have demanded a playoff, finally know they will get one in the 2014 season. First, though, they'll experience a bit more of the BCS system that they have largely lampooned for more than a decade.

The 2012 and 2013 seasons will be the 15th and 16th — the final two — that end with a national championship game between the teams ranked Nos. 1 and 2 in the BCS standings that blend human and computer polls.

The controversial mathematical formula has been repeatedly tweaked over the years, but no changes were made for this season, probably because the off-season focus was on plans to scrap the system when the current bowl and TV contracts expire after the 2013 postseason.

Now waiting in the wings, approved by university presidents and chancellors in June: Starting with the 2014 season, the BCS will be replaced by a four-team playoff.

Here's a refresher on how the national championship will be decided this season and next — and a preview of how things will work in 2014 and beyond:

2012, 2013 seasons

Postseason system: The BCS, which began in 1998, remains in place.

How the national champion will be determined: The top two teams in the BCS standings will meet in the title game. The standings again will include three components, each counting one-third: the USA Today poll of current coaches; the Harris Interactive poll of former coaches, administrators and players and current and former media members; and an average of six computer polls.

Where the national championship games will be played: This season's BCS title game will be in Miami on Jan. 7. The title game for the 2013 season will be in Pasadena, Calif.

2014 season and beyond

Postseason system: A four-team playoff will begin with the 2014 season and continue through the 2025 season. The semifinals will match the No. 1 seed vs. the No. 4 seed and No. 2 vs. No. 3, with the winners meeting in the final.

How the playoff teams will be determined: The BCS standings will be scrapped, and a selection committee will choose and seed the playoff field. The committee will be instructed to consider specific criteria, including: win-loss record, strength of schedule, head-to-head competition, and whether a team won its conference championship. Decisions have not been made about who, or how many, will be on the committee.

Where the playoff games will be played: The championship game will be bid out to cities, similar to the way the NFL awards Super Bowl sites. The semifinals will be played within the bowl system. Six bowls -- the Rose, Orange, "Champions" and three others to be determined — are expected to host four semifinal games apiece over a 12-year period. (The "Champions" bowl is an SEC-Big 12 matchup that will begin with the 2014 season at a site to be determined by an ongoing bid process.)