safely remove hardware
 

For things like flash drives, I have been told that you should click on the safely remove hardware icon on the task bar. Is this actually necessary? I've never had any problems with my flash drive, but I have an external hard drive, and I usually unplug it without clicking on safely remove hardware. What problems could this cause?

Thanks.

Potential corruption of data or lost data.

It used to be necessary, I think, but not anymore.

In any case, you should not pull out the plug while data is being written. It can result in many bad things, as BlindMonk said.

But in the case of the harddrive, since it has spinning disks, if nothing is being written and I pull it out, nothing will happen?

Also, what will be the difference between running it in "optimize for quick removal" mode and "optimize for performance" mode?

Yes, I believe so. But I always safely remove anyway. Takes 5 seconds to do.

If you optimize for performance, it'll probably run better, but will cache stuff on the hard disk. So you WILL have to do the safely remove thing every time you disconnect.