MySpace, Facebook, Twitter, LinkedIn and Google+ are social media websites that can be mined by potential employers for personal information. If privacy settings are not at their highest, this could mean viewers can access pictures, posts and status updates best kept within your private life.
One thing to remember is that the Web often forgets about context -- and so Tweets can be misconstrued, events from years ago can end up hampering your prospects, and your profile may not show you to be the type of person a company would want to hire.
In relation to accounts you actively use, check your privacy settings. For Facebook, head over to account settings through the top-right button, and then select 'privacy' from the menu on the left. You can then decide who can see what information is posted -- and whether you can be looked up based on your email address, phone number or search engines. You can also use another handy tool from your profile page to see what others view, by selecting the '...' button and choosing 'View as..'.
Twitter users, click your profile avatar in the top right of the Twitter.com screen, and select 'Settings.' From this menu, you can make your profile private or change a range of basic account options.
If you want to be completely hidden on social media, consider using a different surname.
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