chronological
Arranged in the order that events happened over time.
Chronological means arranged in the order that things actually happened in time, from earliest to latest. When you put events in chronological order, you're organizing them like beads on a string, with the first thing that happened at the beginning and the last thing at the end.
History books are usually written in chronological order, starting with ancient times and moving toward the present. When you write a story about your summer vacation, putting events in chronological order means describing the first day first, then the second day, and so on, rather than jumping around randomly. A timeline is a visual way to show events in chronological order.
Something presented chronologically follows the natural sequence of time. If you were explaining how to bake cookies, a chronological explanation would start with gathering ingredients, then mixing them, then baking, then cooling: each step in the order it actually happens.
Teachers often ask students to put historical events in chronological order to test whether they understand when things happened and how earlier events influenced later ones. When your friend tells you about their chaotic day but keeps saying “wait, before that happened...” they're trying to get back to chronological order.