With recent breaches of online security at major sites, keeping your sensitive data secure is more crucial than ever. This is some general tips to keep in mind when you're spending time online ::
Secure your web browser
Before visiting a single site, you can do a lot to protect yourself with privacy and security settings built right into Internet Explorer, Firefox, Safari, Google Chrome and other browsers. Make sure to understand the preferences, and set them to the levels you're most comfortable with.
Stay prudent during registration
Sites that ask you to register your e-mail address tend to state their terms and conditions of use. If you have any concerns, take a moment to read the small print. You might be signing up for more than you thought, including regular newsletter e-mails, or worse, authorising your personal info to be shared with third parties. If a site doesn't have any stated terms at all, that itself is a good warning to stay away.
Get another e-mail account
Some people find it helpful to keep a secondary account that is specifically used for registering on sites or when an e-mail address will be displayed on a public page. This may control the amount of unwanted e-mails, but does require time for managing the additional e-mail account.
Create secure passwords
Instead of common words, use long passwords that contain letters, numbers, and a mix of upper-and-lower-case characters. Try not to use the same passwords twice. This can be difficult, as you may have dozens of sites that you visit regularly. Ask yourself if you need to sign up, or if you can use a site effectively without registering. Write your passwords down if necessary, and keep your password list secure.
Monitor your social network activity
Most social network sites provide privacy settings that can be customised to your own comfort level. Note that the default settings may no necessarily be in the best interest of your privacy. Aside from these settings, be reminded that anything you put on your profile or otherwise interact with on the social site has a high chance of being seen and used by the social network company itself for other-possibly unintended-purposes.
Surf safely over WiFi
When using public or open WiFi networks, avoid conducting sensitive transactions such as banking or government services. Even if you're only just browsing, use secure methods whenever possible. Facebook and Twitter, two of the most popular social sites, offer connectivity through secure HTTPS, but this has to be explicitly selected in your account settings(unsecured HTTPS is used by default).
Protect against viruses & malware
Install protection software to help protect against threats, and keep it maintained with the latest updates. New types of viruses and malware are introduced constantly. Do note that some of these can track and record your online habits, while even more harmful ones can use your computer without your knowledge to launch online attacks.