It supports the 1995, 2001 and 2005 versions of the standard, portions of SystemVerilog, and some extensions.

Icarus Verilog is available for Linux, FreeBSD, OpenSolaris, AIX, Microsoft Windows, and Mac OS X.

As of release 0.9, Icarus is composed of a Verilog compiler (including a Verilog preprocessor) with support for plug-in backends, and a virtual machine that simulates the design.

Not even the author quite remembers when the project was first started, but CVS records go back to 1998.

Icarus Verilog development is done largely by the sole regular author, Stephen Williams.