My roommate belives that by restarting or turning off his computer somehow damages it and he always puts it in sleep mode. In my opinion its a hole lot of bs but i would like ask all of you about the idea.
Anything that was created will eventually become damaged. It's part of an artefact's lifecycle and is generally known as "wear and tear".
That said the computer has the ability to be put into a light sleep, deep sleep or shutdown. The choice of what to do is up to its owner and may be influenced by whoever pays the electricity bills. However, to address your question directly, turning off a computer does not damage it (or the off switch would have been eliminated a long time ago). Most computers will last a number of years even if you turn them on and off everyday. But even if you didn't turn it on off as such, there is a good chance it will not last for 100 years.
Shutdown and Restart PC:
During the shutdown or restart process, OS will close down any files it was reading or writing. It will then close down the system registry, the most important set of files for the operating system. The hard disk arm, which reads files across the hard disk, is being parked at one side of the disk.
The only proper way to shutdown or restart a PC is to go through the operating system and tell it to shut down. It can take anywhere between 10 seconds and a minute for a PC to fully shutdown or restart.
All these steps ensure that the computer files won’t get corrupted, and any changes that you made to the system are saved (except for any open programs- you need to save each one manually to be sure you don’t lose anything).
Computers have this procedure for a reason. It’s one of the only ways you can ensure that your computer is protected from hacking or power surges. It’s also the only way the computer can ‘start fresh’- which can improve performance, reduce load times, and increase productivity
1) Lower energy costs – Computers, especially desktops, use enough power where having every single computer on in your office will make a difference in your bills.
2) “Fresh Start” – By shutting down and rebooting a computer all programs are also being restarted. Throughout the day, programs can develop little issues that could get in the way of day to day use of the computer. If the computer isn’t shut down, over time these issues will remain, build up, and eventually present additional problems, decreasing performance, and software load times.
3) Longevity– When a computer is shut down, it draws no power, and the hardware inside the computer isn’t moving or being used. With less stress placed on the components, the computer’s hardware will last a little bit longer. We’re not talking years, but it will extend the life of the computer.
4) Power Surge Protection– Power spikes and surges occur in your office and home every single day. Long-term exposure to power surges significantly lowers the life of a computer, and large spikes, like a lightning strike or power outage, can completely destroy computer components.
When a computer is turned on, there’s an increased risk of a power surge causing a catastrophic computer failure. Although you might get luck and be able to recover your data, there’s a good chance that your computer won’t boot, and your hard drive could be unrecoverable.
I have been turning off my own laptops nightly for nearly 25 years. Laptops have changed of course and only the most recent one has an SSD drive. All the others were hard drives. I never lost a hard drive in all that time because of powering off and restarting. I think your roommate's story does not make any sense at all. This is something way down on my worry list.
For the most part, I unplug when I turn off unless the battery needs charging. I leave plugged in 10% if the time and unplug 90% of the time.
In the simple case he is wrong. In the longer term case/overall its less clear cut, but still highly likely he is wrong.
Your roommate might have incorrectly formed his opinion based on the following -
A sudden outage can cause hard drive corruption because data is not completely written to disk - this does not happen during a controlled shutdown as the computer issues an instruction to flush data to disks.
On startup, a shut-down computer may attempt to install OS updates it previously downloaded, and this could cause issues. This has nothing to do with the shutdown of the disk, and is an OS limitation. If going to sleep mode does not cause this issue, its only because the issue has been deferred - and even this needs to be weighed against the OS being more out of date.
The question left to contend with is "in what ways would sleep mode be less dangerous/stressful to the computer. As there is a low amount of current going through the system during sleep mode, waking up will be slightly less stressful on those components that were not shut down (I'm thinking mainly of memory, so its possible - theoretically - that this make memory last longer). This is really more of a theoretical argument, as inrush currents are associated with higher power draw items like hard disks - and these are spun down and will need to power up again anyway.