A
calendar is a system of organizing days for social, religious, commercial or administrative purposes. This is done by giving names to periods of
time, typically
days,
weeks,
months, and
years. A
date is the designation of a single, specific day within such a system. A calendar is also a physical record (often paper) of such a system. A calendar can also mean a list of planned events, such as a
court calendar or a partly or fully chronological list of documents, such as a calendar of wills.