I'm quite proud of the fact that my computer runs very well. Recently I had the pleasure of helping a dear friend fix up her computer.
It was literally overrun by spyware, trojans and viruses.
First off some definitions. Spywares are basically a program that watches what you do and then transmit the data to someone else. Seems fairly harmless- but if you are doing banking and credit card payments etc.. -it can lead to someone emptying out your bank account or using your credit card to buy stuff for themselves.
Trojans- the name comes from the Greek story about how the Ancient Greeks built a Big Horse gave it to the Trojans whom they were besieging. The Trojans foolishly took the Horse into their Fortified City and at night- Greek soldiers came out, opened the city doors, and the Greek Army rushed in and burnt the city to the ground. Basically a Trojan program is a harmless looking program which seeks to control your computer and doing bad stuff with it. Its serious shit- imagine if a trojan program uses your computer internet access to download child porn.
Viruses- you guessed it- do bad stuff to your computer. Organic viruses like SARS, influenza, chicken pox, to the common cold strike your health. Once you get infected you can infect other people. Sometimes you can die from them. Well computer viruses are the same sort - they may cause your computer to crash and not work, lose data, send more viruses out to infect more computers, or just slow you down.
How you get them- usually you catch them- when you enter into corrupt internet sites- a bit like walking into a gangster or red light area. Often u get them- when someone sends you a virus via an email attachment. Nowadays you can get infected if you don't have a proper firewall. A bit like not having locks on your doors in your house.
One program is usually not enough to deal with all the threats. You need several. On my computer I have AVG Grisoft, ZonealarmPro (Firewall) Pro on permanent watch- meaning they are constantly on. I also run Spybot and Adaware from time to time.
Thankfully, we live in a great world. There are software out there which you can download for free- no strings attached which can help you out. Often you need to run not just one- but two or three programs to flush the crap out. (Just to let u know- I HATE Norton and McAfee- there are horrible to use and swallow up too much computer memory space.)
First off I use AVG Grisoft to scan for viruses. It also checks your email to make sure there are no viruses. Get it here: http://free.grisoft.com/freeweb.php
Remember! The free software doesn't require a password.
To make doubly sure you can also use AVAST: www.avast.com/
To make sure that everything is OK- I also use Trend Micro- they have an online virus scanner. So u need to have the internet to use it. http://housecall.trendmicro.com/ Its very good and catches the latest viruses unlike its competitors.
For spyware- I use Spybot Search and Destroy - get it here
I also use "Adaware" - get it here: www.lavasoftusa.com/software/adaware/
You also have to update your computer- esp if you r using Windows. In your Internet Explorer u goto Tools- then click on Windows updates.
New viruses and trojans are being made everyday- so be sure to make your system secure.