Finder freezes. That shouldn’t happen at all, and it don’t happen often, but it’s not unheard of for your Mac’s Finder to freeze, freak out, or otherwise stop responding properly. To bring it back to life, hold down the Option key, click and hold the Finder icon in the Dock, and choose Relaunch. In theory, you should be able to keep working normally after the Finder relaunches, but I recommend restarting your Mac afterward to help get rid of whatever caused it to happen in the first place.
