You can look up a list of chat commands in the chat settings menu under chat box. Click the “Chat Help” button. With chat commands, broadcasters can play commercials with /commercial, ban, temp-ban, remove caps spam, control slow mode, and add users as moderators, among a number of other features.
Q: How do I use slow mode?
Slow mode is great for keeping chat manageable on popular streams. It requires users to wait a number of seconds before they can chat again. The default settings is 60 seconds but this can also be changed with a chat command (/slow #interval). Type /slowoff to remove the function.