For example, a biologically 45-year-old man can have a play age of an 8-year-old. Some people always have a specific preferred play age, whereas other people are flexible to play any age within a certain range (e.g. 1-4 or 7-14). Yet others may have developed several distinct characters they like to play such as a 3-year-old, a 5-year-old and a 10-year-old.
The chosen play age is usually agreed on with the other player(s) before a scene begins. Sometimes the play age is not specific but just a vague "child", "schoolgirl", "preteen", or "teenager". The same applies to online roleplay.
The play age will determine the player's language abilities, body language, and words. It will also influence the activites in the scene, such as diapering a baby, the need for a nap, the games typically played by children at certain ages, the typical offenses committed and the kind and severity of possible punishments for such offenses.
In addition to agreeing on a play age, the players may also agree on a setting's time.