iTerm is a full-featured terminal emulation program written for OS X using Cocoa. It was designed to provide a better command-line experience with a native Apple-style interface and strong international language support. The original iTerm project is currently on hold, and iTerm2 is the newer project based on iTerm.

Flexible OS X terminal experience

iTerm improves the older OS X terminal experience by making command-line work feel more flexible and comfortable. It helps users keep command-line work organized, while full-screen mode and focus-follows-mouse support make it easier to stay focused during longer shell sessions.

Visual options such as transparency, blur, and custom backgrounds add a level of personalization, but the app’s real value is in making everyday terminal use smoother through practical touches like select-to-copy, middle-button paste, smart window placement, AppleScript support, and Bonjour integration.

Customizable VT100 terminal emulation

iTerm includes VT100 emulation with terminfo support and flexible custom key mapping. It supports additional xterm escape sequences, including xterm titling and xterm mouse reporting for click and scroll events. It also offers customizable ANSI 16-color support, 256-color mode, COLORFGBG variable setting for color scheme detection in apps such as Vim, and an anti-idle function to help prevent disconnections during inactivity.

The app’s customization also extends to multilingual use. Users can specify a second font for non-Latin characters, display double-width characters used in many East Asian languages, and use all language encodings available with OS X. This makes iTerm more adaptable for users working across different languages, servers, or localized environments.

Configurable tabbed terminal sessions

iTerm supports tabbed terminals, allowing tabs to be dragged and dropped between windows. Tab labels can change color to indicate session activity, and users can send keyboard input to multiple tabs. The app also lets users customize sessions through bookmarks and profiles, including support for macros in bookmark commands and URL handling for protocols such as FTP.

Best suited for older OS X setups

iTerm remains notable as a capable terminal emulator for older Mac environments. It offers tabs, customizable sessions, VT100 and xterm-related features, appearance customization, and multilingual support. However, users looking for a modern, actively developed terminal should use iTerm2 instead.