Serial Serial is a great Terminal Emulation Program with built-in driver support for most common USB to serial devices. Or, ctrl-click/right-click on the app and select Open from the pop-up menu so not to permanently lower your security settings. If you have trouble installing any of the following (or any other program) with an unidentified developer error, goto: System Preferences ➤ Secrity & Privacy ➤ General and click on Allow Applications Downloaded from: Anywhere and try again.
If you can't find a driver for your adapter (eg, Belkin), try Serial which has built-in support for most (if not all) USB-Serial adapters. If you're looking for a command line app, there's Screen (built-in) or Minicom. The following Mac OS X GUI applications are available: Having installed the right driver for our USB-serial adapter, we also need to install some terminal emulation software before we can connect to anything.
