By default the Chat feature in your Google account is ON.
While you can simply sign out of chat if you do not feel like chatting with your friends, Gmail also offers the ability to turn off chat entirely.
Here's how to turn off chat in Gmail:
- Click the gear icon and choose Settings.
- Click the Chat tab.
- Choose "Chat off."
- Click Save changes.
To turn chat back on, just click Chat on.
If you're using Chat in Gmail, selecting "Chat off" will sign you out of Chat in that window. If you're logged in to Chat in more than one window, you won't be fully signed out until you refresh each page.
If you're using Hangouts in Gmail, selecting "Chat off" will only sign you out in Gmail. It won't sign you out of Hangouts on other Google desktop properties like Google+ or the Hangouts Chrome extension.