The Joomla 2.5.* version of the Web Links Component is missing a class for the descriptions in the list view of a category. This means you can't control the look of the description using css. To fix this you can do a simple template override.
Components are the main building blocks of a Joomla site.
Generally, backup is something you need to breathe, not just use, if you are in this business. It's the number one security tool. Having a fresh and usable backup can be a life saver in a number of situations, not only when your site is hacked, but on a great number of other situation, beginning from human error (accidentally deleted key parts of site - or just forgot to pay your hosting bill) to situations out of your control, as a hardware/software failure. And is essential to have an easy to use tool to move your site around - from local development environment to live hosting, or from one server to another. Enter Akeeba Backup (former Joomla Pack), a must have tool for any Joomla webmaster.
Yes, things like media files - or your software. No, I don't sell software - I give it away for free, for example here. Bu I build sites with selling capabilities. My favorite solution for it is VirtueMart, THE shop to be used with Joomla.
Is powerful - but is not for beginners, you can easily lost here without proper guidance.