Yearbooks are generally put together by a student committee, which may or may not be advised by members of the faculty and staff. The committee usually has one or more editors who are responsible for collecting and putting together all of the information to be put into the book, also deciding the layout and giving of space for each contributor.
Often, yearbooks are distributed at the end of a school year to allow members to get the books and signatures/personal messages from classmates. In the US, those that distribute at this time may publish a supplemental insert with photographs from spring sports and milestone events (such as prom and graduation), as well as other important events. Many schools at which yearbooks are distributed at or before the end of a school year have a tradition of having students sign and leave notes on each others yearbooks.
Some schools distribute yearbooks before the end of the school year – such as during July, at Homecoming (US) in October or another designated time in order to include year-end activities. In some cases, yearbooks are mailed to the parents' homes of graduated seniors.