An afterpiece is a short, usually humorous one-act playlet

Play (theatre)

A play is a form of literature written by a playwright, usually consisting of scripted dialogue between characters, intended for theatrical performance rather than just reading. There are rare dramatists, notably George Bernard Shaw, who have had little preference whether their plays were performed...

 or musical work following the main attraction, the full-length play, and concluding the theatrical evening. This short comedy, farce

Farce

In theatre, a farce is a comedy which aims at entertaining the audience by means of unlikely, extravagant, and improbable situations, disguise and mistaken identity, verbal humour of varying degrees of sophistication, which may include word play, and a fast-paced plot whose speed usually increases,...

, opera

Opera

Opera is an art form in which singers and musicians perform a dramatic work combining text and musical score, usually in a theatrical setting. Opera incorporates many of the elements of spoken theatre, such as acting, scenery, and costumes and sometimes includes dance...

 or pantomime

Pantomime

Pantomime — not to be confused with a mime artist, a theatrical performer of mime—is a musical-comedy theatrical production traditionally found in the United Kingdom, Australia, New Zealand, Canada, Jamaica, South Africa, India, Ireland, Gibraltar and Malta, and is mostly performed during the...

 was a popular theatrical form in the 18th and 19th centuries. It was presented to lighten the five-act tragedy

Tragedy

Tragedy is a form of art based on human suffering that offers its audience pleasure. While most cultures have developed forms that provoke this paradoxical response, tragedy refers to a specific tradition of drama that has played a unique and important role historically in the self-definition of...

 that was commonly performed.

An example is The Padlock

The Padlock

The Padlock is a two-act 'afterpiece' opera by Charles Dibdin. The text was by Isaac Bickerstaffe. It debuted in 1768 at the Drury Lane Theatre in London, England, as a companion piece to The Earl of Warwick. It partnered other plays before a run of six performances in tandem with "The Fatal...

by Charles Dibdin

Charles Dibdin

Charles Dibdin was a British musician, dramatist, novelist, actor and songwriter. The son of a parish clerk, he was born in Southampton on or before 4 March 1745, and was the youngest of a family of 18....

, first performed in London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

in 1768.