Did you know that your tweets, by default, are visible to the whole world? For better or worse, your boss, wife, kids, competitors and enemies can read what you’re tweeting. It’s critical to think of tweeting like blogging. Your tweets will likely stay public forever. Even if you delete them they may be archived somewhere. Most people make their tweets public (it makes sense in most cases), however you should be aware of the implications. If you’re concerned about privacy, make your profile private. That means your tweets will only be visible to those you manually approve. You can set this option on your account page. Select the ‘make my tweets private’ checkbox at the bottom of the page.
When you sign up for Twitter, the default behavior is to make your account public. If you want to make it private, you must change your settings. The profile pages for public accounts are visible to everyone, and anyone can follow public updates (without the account owner even knowing about it).
If your account is protected, you will receive a full request when someone wants to follow you. Only approved followers can see your profile page. Protecting your profile, may be a good way to get started if you are concerned about your profile public. However, it does make conversation difficult as your @replies will not be seen by people who are not following you. So, if your goal is interaction, you should make your account public.
To protect your profile:
When you go to your home page after protecting your profile, you will see a message reminding you that your profile is protected.
If someone who has requested to follow you visits your profile, they will see a message saying "You've requested to follow this person. Remove?" until you have granted them access or the request has been canceled. Protecting your profile means that you:
It is never necessary to follow someone that follows you. If you decide to revoke follow privileges, go to your followers page, and click on the remove button.
Tweets from protected profiles do not appear in search results. People can still find your account by using the Find People search tool. However, only people you approve to follow you will be able to see your tweets. Also, any tweets posted while your profile is private will always remain private. Similarly, tweets posted to a public account will remain public indefinitely.