Is It Possible To Hack People's Computer From Internet?

yes it is surely possible.i have seen one of my friends do it.he does it easily.he didnt tell me how but for sure it is possible

It is very possible. People can insidiously stores softwares in your computer that can steal your information. Or, there's phishing of course where you can also fall prey to unruly hackers. There are a lot of ways these hackers can get into your computer so best be careful and have the appropriate programs to safeguard your PC.

Hackers can take your computer under attack when you don't have a firewall, they use internet connections for that so technically it happens via the internet.

Also never ever download/accept a file unless you trust the website/person. P2P programs include lots of trojans aswell.