A rerun or repeat is a rebroadcast of an episode of a radio or television program.
There are two types of reruns – those that occur during a hiatus, and those that occur when a program is syndicated.
Reruns can also be, as the case with more popular shows, when a show is aired outside its timeslot (for example, in the afternoon).
It only broadcasts the past week's episodes back-to-back.
When used to refer to the rebroadcast of a single episode, Lucille Ball and Desi Arnaz are generally credited as the inventors of the rerun; it was first utilized for the American television series I Love Lucy (1951–57) during Ball's pregnancy.
In the United States, most television shows from the late 1940s and early 1950s were performed live, and in many cases they were never recorded.
However, television networks in the United States began making kinescope recordings of shows broadcast live from the East Coast.
This allowed the show to be broadcast later for the West Coast.