There are multiple natural events that can cause damage computers such as lightning strikes, fires, and extreme temperatures. Fires can damage your CPU fan, lightning strikes can cause a surge, and extreme temperatures can damage the computer.
There is also human error and hackers. People can drop their computer accidentally, open a virus without knowing it, or can just be ignorant of their computer and damage it. Hackers will also steal personal information using emails, worms, trojan horses, malware, and scams to acquire your personal information.
But there are ways to protect your computer. You can get antivirus and antispyware software, put up a firewall, secure your data, use encryption, keep personal information a secret, and have very strong passwords.