Twitter allows you to control which users can enter into a conversation with you by replying to your Tweets. By default, every Twitter user can reply to your Tweets. If you want to limit replies, you can opt for one of the following two options when creating a Tweet in the Publish Editor:
- Only Twitter users that are mentioned or are followed by the account creating the Tweet.
- Only Twitter users that are mentioned in the Tweet.

Tweets with one of the above two settings will be labeled on Twitter and the reply icon will be grayed out for those users that you have excluded from replying. Users who can’t reply will still be able to view, retweet, and like the Tweet.
Once you’ve published a Tweet with conversation control, you cannot change the restrictions other than by deleting the Tweet and creating it anew. Replies and retweets of your Tweet will inherit the restrictions you placed on the original Tweet, but Quote Tweets will not inherit your restrictions. If the original Tweet is deleted, replies and Retweets will lose any previous restrictions.