IS was a science fiction fanzine edited and published by Tom Collins.
Is was published in Austin, Texas, U.S.A. in the early 1970s. Six issues of IS appeared before the fanzine was renamed Apollo.
Issue 3 was released in July 1971, and featured the article "Tiptoeing Through Tulane" by Grant Carrington.
Issue 4, from October 1971, was the special August Derluth Memorial Issue and featured contributions of writing from William Blackbeard ("August Derluth and the Comics"), Robert Bloch, Ray Bradbury, Larry Niven, and Graham Wilson. Art work was contributed by Kelly Freas, and Tom Kirk, among others.
- 5 in 1972.
Issue 6 was also published in 1972, and featured front cover art work by Cortén.
Issue 7 was released in 1975, and featured illustrations by Cortén.
Tom Collins later published the fanzine Transient.