‘Botnet’ refers to a group of computers whose security has been compromised in order to use them as ‘zombies’ to send spam e-mail messages or to attack servers. The way such a group of computers was created is with the help of compromised applications called "bots". Those bad programs will turn your PC into zombie one that hackers can control at distance with the help of a "bot-herder" command system and a control server. Those group of computers (Botnets) are considered to be something very dangerous in the virtual world. They can damage whole websites and networks besides your own PC.. Problems like viruses, malware, spyware can also be distributed via those Botnets, besides all the spam emails. Denial of Service (DoS) and Distributed Denial of Service (DDos) are 2 others popular methods to hurt servers that hackers are doing with those Botnets. They will try to massively overload a system so it won't work anymore because there are too many requests to acceessit at once. Here Computer Repair Service you can find a great online service ready to repair any problems your PC may have.
The usual way you can get infected by a Botnet is via viruses and trojans carrying such threat. These Trojans and viruses may be delivered to the user in the form of spam emails or they could get downloaded from malicious websites, posing as essential video and audio codecs. Once it is part of yur PC, the Botnet program will communicate with its bot-herder server to wait for more instructions. Such instructions might include to start sending lots of spam emails, or to attack a remote website or server, or simply to propagate the Botnet to others PCs. Most of a botnet’s activity occurs without the user noticing any major difference in their computer; therefore it is important that users have a clear understanding of how to recognize a botnet infection. This site Spyware Removal has good infos about spyware removal.
If your computer system is slower than usual, this is a sign something wrong is happening. Your internet connection will also slow down drastically due to the many connections being maintained by the botnet program. You might notice 2 more things: you have less hard disk space than before and your browser is not working as usually. So your browser might shut down without warnings, your homepage and your Windows desktop might be changed for no apparent reasons.