Stream ciphers are an approximation of one-time pads. RC4 is the most well-known stream cipher, but on the edge of being insecure now.
Wikipedia - Stream cipher
RC4 is the official algorithm, designed by Ron Rivest in 1987. It was initially a trade secret, but an anonymous poster publishe a description of it to the Cipherpunks mailing list. The algorithm derived from that description was known as ARC4, for “Alleged RC4” (because RC4 was registered as a trademark by RSA). RC4 was historically widely used in TLS, although now prohibited as of RFC 7465.
Wikipedia - RC4
Spritz is a 2014 upgrade of RC4 by Rivest and Schuldt.
Salsa20 was designed by Daniel J. Bernstein.
Wikipedia - Salsa20
ChaCha20, closely related to Salsa20, was also designed by Daniel J. Bernstein, and might be slightly more secure than Salsa20. Google is now using this for Android.
Wikipedia - SOSEMANUK
Designed by Robert Jenkins (“burtlebob”) in 1996, and used in a handful of places, including inside GNU Coreutils.
Wikipedia - ISAAC
Designed by Doug Whiting, Bruce Schneier, Stefan Lucks, and Frédéric Muller.
Wikipedia - Phelix
Designed by Bruce Schneier for Neal Stephenson to use in the book Cryptonomicon.
Wikipedia - Solitaire
This is the gold standard, but hard to use in practice, except in specific use cases.