Most new seasons of TV shows begin in either spring or autumn. However, seasons of shows can begin at any point during the year, with many shows airing over the summer.
As of 2015, the growth of cable networks, as well as streaming services such as Netflix, have changed the way TV shows are produced and released. Some of the most popular shows on TV, such as HBO's "Game of Thrones," air over the summer. Netflix releases original programming at any number of points during the year. Some shows begin airing at unusual points in the year in order to replace other shows. These replacements are necessary when the original show performs below network expectations.