NCAA Division I is the highest level of competition in the National Collegiate Athletic Association, the main governing body for U.S. college sports.
For its first half-century of existence, the NCAA, founded in 1906 as the Intercollegiate Athletic Association of the United States and adopting its current name in 1910, was a single body for competitive purposes.
However, the NCAA now considers the 1947–48 season as the first in which an equivalent to today's Division I existed in basketball.
The AP's "major colleges" of 1948 correspond directly to today's Division I, with "small colleges" corresponding to today's Divisions II and III.
[1] Dates used reflect when the school first became eligible for NCAA-sponsored postseason play—either the NCAA tournament for men or women, the NIT since it was acquired by the NCAA in 2005, or the WBIT upon its launch in 2024.