Browse The Internet Safely [Firefox]

2. Find Website Reputation and Block Harmful Sites:

Firefox has an addon/extension called "Web Of Trust" (WOT). WOT is a community based Safe Browsing Tool and website reputation checker which helps us to know about harmful websites and also can be set to block harmful sites. It also offers settings to set your sensitivity level. WOT's another cool feature is that it adds an icon beside all the links in web pages (including search results) indicating its rating so that we will avoid clicking on these links.

WOT for your Firefox.

3. Get Rid of LSO-Cookies or Flash Cookies:

Cookies are small files saved on your browser by websites especially to customize settings for you. To put it in layman’s terms, cookies help websites to monitor some of the decisions that you have made on the web site so that they can show them to you. For example, a search engine like Google uses cookies to track your search interests and deliver the content that is more relevant for you. Another example is, websites remember your usernames and passwords using cookies so that you need not type them every time you visit the site.
Although cookies are helpful most of the times, many websites and advertisement companies use these cookies to track your online activity. Recently, a new type of cookies called "LSO cookies" or "super cookies" emerged which are hard to delete.

REMEDY: To prevent websites tracking your online behavior, install this addon called "Better Privacy". It helps you delete potentially harmful cookies which are otherwise not so easy to delete.

BetterPrivacy.

4. Beware of shortened URLs:
URL shortening is a technique using which a URL may be made substantially shorter in length and still direct to the required page. This is achieved by using an HTTP Redirect on a domain name that is short, which links to the web page that has a long URL. For example, http://9.bb/Bldp is a shortened URL which takes you to www.adeekshith.tk. Although shortened URLs are of a great help for sharing long URLs on mobiles, twitter, etc, They are sometimes misused by redirecting users to undesired websites.

REMEDY: There is a Greasemonkey script which expands shortened URL on mouse hover. To use it, first install Greasemonkey by clicking here.
After installing greasemonkey, "Expand url shortening service urls" script.





5. Wrap Your Firefox In A Cocoon Of Privacy[Not essential]:
Cocoon is a Firefox extention (not free $6.95 per month, trial for 30 days) that helps you to browse anonymously and prevents harmful content like viruses to be loaded directly onto your computer. When you open a website with cocoon enabled, cocoon servers request that website and send to you instead of your browser directly interacting with the site. It is not essential for everybody, but a very useful tool at times when you are forced to browse through unsafe websites. Visit http://getcocoon.com to download Cocoon.



6. Get Rid Of Harmful Scripts (For Advanced Users):
NoScript is a great extension for a security and privacy conscious user.
Unfortunately, it is not an automatic tool that filters "bad" scripts and lets though "good" scripts. You, yourself, need to know what to block and what to allow. You don't need to be an expert, but you should have at least some very basic knowledge how the internet works and edit your allow or block rules accordingly.
Although this is helpful, it is not recommended for beginners and casual users as it could be annoying as lot many websites (like Facebook, Google docs, Gmail, Yahoo Mail...) cannot work properly without executing scripts, so you need to always check which scripts to allow and which to block.
NoScript for your Firefox

NOTE: There are many more tweaks that can be made to Firefox to enhance your security. I have listed only a few of them which I felt are essential and are quite easy to perform.