[1] Twin is tested on Linux (x86, PowerPC/Power ISA, DEC Alpha, SPARC), FreeBSD, and macOS.

Written by Massimiliano Ghilardi, Twin started in 1993 as his first big program for PC DOS immediately after having learned the C programming language; but he soon abandoned it, since within DOS there was no multitasking, consequently he could not have any other program run inside the windows drawn by Twin.

[2] The terminal emulator Eterm has an interface layer named Escreen for interoperating with the terminal multiplexers GNU Screen or Twin.

This allows Eterm to support multiple sub-shell sessions within a single window.

However, being an interface to existing software, Escreen has the advantage of providing additional capabilities like multiple regions per display, detach/reattach capability, seamless remote session support, firewall support, and more.