Generation Alpha, often shortened to Gen Alpha, is the demographic cohort succeeding Generation Z and preceding the proposed Generation Beta. While researchers and popular media loosely identify the early 2010s as the starting birth years and the mid 2020s as the ending birth years, these ranges are not precisely defined and may vary depending on the source. Named after alpha, the first letter of the Greek alphabet, Generation Alpha is the first to be born entirely in the 21st century and the third millennium. The majority of Generation Alpha are the children of younger Generation X, Millennials and older Generation Z.