What is the difference between intercom and walkie-talkies?

Intercom provides full-duplex, always-on communication, similar to a phone call. Multiple people can listen and talk simultaneously without pressing a button. This is essential for show calling, where the stage manager needs to give cues and receive confirmation from multiple departments in real time.

Walkie-talkies (two-way radios) are half-duplex and push-to-talk: only one person can speak at a time, and everyone on the channel hears the same transmission. Walkies are useful for logistics, security, and operations teams who need intermittent communication, but they're not suitable for live show calling because the push-to-talk limitation makes real-time coordination too slow and unreliable.