A firewall is software that checks all data entering and exiting a computer and it then blocks that which doesn't meet specified security criteria (user-defined rules).1 5. Don't click on website links in spam messages. In an effort to obtain personal information, some spammers will send email that asks you to click on a link. Being so popular an activity, it's imperative that you compress the files destined for another computer. File compression combines a number of different files into one file, and it can also significantly reduce a very large file to a smaller one. As a result, the transmission of a compressed file across the Internet is faster and smoother. Orphans are usually files that contain temporary data created by a program, files created by the user, partial files left over from a computer crash, or any other kind of miscellaneous files created for almost any other reason. The problem is that an uninstall program doesn't delete the orphan files it leaves behind because they were never part of the program when it was first installed. We aren't going to cover them all, but we will introduce some of the most popular so that you can get a feel of the control over your system that these configurations give you. Users. Before we get into the individual settings, it's important that you understand that each set of configurations you make is specific to the users that sit down in front of a computer. The Wikipedia encyclopedia claims that "Out of 1 billion camera phones to be shipped in 2008, Smartphones, the higher end of the market with full email support, will represent about 10% of the market or about 100 million units." But what is it that makes smartphones so appealing? As mentioned, smartphones give us the ability to not only carry our data around with us where ever we go, it also gives us the ability to edit that data any place - any time. It's when these accessories are work requirements or when they're needed to produce works of quality for any other reason that they can become rather expensive. And this expense applies to microphones, digital cameras, PDAs, scanners, video cams, and more. Regardless of cost, it's important to understand that accessories can become "necessities," and that the best time to get them is the moment you buy a new computer.