I seen my friend being hacked on the spot while we were playing game..
This is the case,when we were gaming he say his com start to lag and then he cannot control what he is doing.Then i saw messages coming out like "lol" and he say he did not type that.It become serious in the end when strange activities came out and the "lol" start to spam the conversation window.
So i told him to quit the game and start to take action.
There are a lot of reasons why one being hacked.The very main reason is because you are infected with a malware.Malware like Trojan allow one to take control of your computer.The longer it reside in your computer,the more be sure to get taken over.
Based on what he said,he say that when he is using PC Tool Firewall which what i recommended him...nothing was wrong,but when he use Windows Firewall to play game that's what happening.
Apparently there are some outgoing connection that is not blocked when use WindowsFirewall,because by default it allow outgoing.
In conclusion,Software firewalls are important part of security.Even though Windows Firewall can protect you but it give you only basic protection.By installing a software firewall it does more than what your windows firewall do.
No antivirus is 100% detection...there might be some malware that your antiviruscan't catch.But that doesn't mean you don't need to install any...at least it will still protect you.
My recommendation for free antivirus are Avast,Microsoft Security Essential and Avira Antivir while Firewall recommendation are PC Tools Firewall Plus,Comodo Personal Firewall,Online Armor Free and ZoneAlarm Firewall Free.
Paid antivirus i will only recommend Kaspersky Antivirus.
So first step to do if you found out you are hacked is off your internet immediately.Without connection,the hacker cannot control your computer.Thus,this is thebest time to start find out the reason of why you are hacked.Starting scanning with your antivirus to confirm that its an malware infection.
Reformat is the ultimate solution..