Max

Max[x1, x2, ...] yields the numerically largest of the xi.

Max[{x1, x2, ...}, {y1, ...}, ...] yields the largest element of any of the lists.

Examples

Maximum of numbers:

Max[3, 1, 4, 1, 5, 9]
(* 9 *)

Maximum of a list:

Max[{-5, 3, 7, -2}]
(* 7 *)

Please visit the official Wolfram Language Reference for more details.