When you block someone on Facebook, they will not be able to see your profile page and even if they search for your name or email address, there will be no results. The person that you block won’t know that they are blocked. The blocking system was created by Facebook to be able to protect your privacy. If there is someone that you want to no longer see or find you in this social networking site, for whatever reason, blocking them is the instant solution. People can be blocked even if they are not in your network of friends, and if they are your friend, after you remove them as a friend, they can still be blocked by using any of these methods:
When invited to be a friend. When you get an invite from someone to add them as a friend, there is an option to block them. This will ensure you don’t get another invite if you choose to ignore the invite and that your profile will not come out in when they search for you. When you ignore their invite, click on the report as spam, and in the pop-up, check the ‘Block this person‘ box and click submit.
Go to their profile page. At the bottom left of the profile page of the person, there is an option to ‘Report/Block this Person’. Click on this and in check the ‘Block this Person‘ box, and click submit.
Using privacy settings. Go to the account tab on the upper right hand of any page, and from the drop down menu, choose privacy settings. At the center of bottom of the page there is ‘Block Lists‘ option. Click on the ‘Edit your list‘ link to add the name or the email of the person you want to block.