Ticket can mean one of several things:

Permission

A ticket is a voucher to indicate that one has paid for admission to a theatre, movie theater, amusement park, zoo, museum, concert, or other attraction, or permission to travel on an airplane, public transit, boat trip, etc.

Paper is generally used, although plastic may be used instead. Some have a barcode or magnetic stripe for keeping simple data stored on them.

Counterfeit tickets are a problem at high-priced concerts and other events, so holograms are used on tickets for the Olympics, Super Bowl, and other high-profile events.

No tickets are needed in the case of voluntary contributions, e.g. after a street performance; in fact, a ticket system is often neither practical nor legal in such a case.

See also Vending machine#ticket machine

Receipt

A ticket may be a pick-up ticket, for example when retrieving clothing from a dry cleaning shop or an automobile from a repair shop. It is also used in places where people are required to "take a number" to queue up, such as in a waiting room or at a customer service desk. Often, this simply has a number printed on it.

Notification

In (primarily US) law, a ticket is a notification that one has committed a minor legal infraction, for which a fine must be paid, and/or an appearance in court must be made (See: summons). Typically this means a parking ticket for parking in an unlawful manner or allowing a parking meter to expire, or a ticket for a moving violation such as speeding.

A ticket trap is where police deliberately set up in a place where motorists are likely to break the law, even if just on a technicality. This may include places where the speed limit is set too low (called a speed trap), or where there is an intersection with an awkward or confusing design. Often, this is used to earn extra money for a municipality, such as a poor rural town or county. This is also often illegal under the laws of the state, province, or other jurisdiction the municipality is under.

Elections

A ticket often refers to a single election choice which fills more than one political office or seat. For example, in the U.S., the candidates for president and vice president run on the same "ticket", because they are elected together on a single ballot question rather than separately.

A ticket can also refer to a political party. In this case, the candidates for a given party are said to be running on the party's ticket. Straight party voting (most common in some U.S. states) is a means for a voter to cast a single vote for the entire party ticket, including every office the party has a candidate running for.

Computer Security

A ticket is a number generated by a network server which can be delivered to itself, or a different server, and cannot easily be forged. Tickets may either be transparent, meaning they can be recognized without contacting the server that generated them; or opaque, meaning the original server must be contacted to verifiy that it issued the ticket.

Some magic cookies provide the same functionality as a ticket.