Effects of "Blocking" a Follower on Twitter

For various reasons, sometimes we block some of our Twitter followers. We are not always sure of the technical outcome.

If you block someone on Twitter, he will no longer be able to follow you back as he is removed from your Followers List. If he tries to re-follow you, it will not work and there will be no error message to him. At the same time, he will not find your tweets on his timeline as your tweets no longer show up there. He may not be aware of the blocking as he is not notified that you have blocked him. 

On the other hand, we need to be we aware that blocking has no affect on his ability to read your timeline on your profile page. He can still find your tweets on your timeline and can reply to your tweets by mentioning your account with the "@" symbol in front of your account name. He can not only re-post your tweets but also subscribe to your timeline via an RSS feed. Meanwhile, a person could have more than one twitter accounts and may follow you from his other twitter account that you are not aware of.