dmg files are automatically verified when they're mounted.
No.
DMG is a native format for OSX. OSX will open DMG if you double click on it.
Yes, there is no need for them, unless your using them.
DMG is a file type. You don't install a DMG, you open it. Maybe there is something inside the DMG that can be installed, maybe not. It is a common way to send many kind of files. It is a bit like .sit or .rar.You can make your own DMG files and save things inside them, and send the dmg to your friends. Use Disk Utility to make DMG files. The DMG size is selectable and can be as big as your free memory. It will appear on the desktop. You can put a password on it, but don't forget it! If you do, you won't be able to open the DMG!To open the DMG you made, just click on it. A disk Image will appear on the desktop just like a hard drive.Drag or copy files there. Eject it. The DMG file is still on the desktop. It is a file that you can email or copy to an external drive. Everything that you put in the disk image will actually be in the DMG file. If you don't want the DMG any more, drag it to the trash.Cool!
Unless you are making a site yourself and saved the HTML files for later uploading, it is normally safe to deleate HTML files. Html files are website pages which are normally saved for later use by the internet explorer. These are normally saved in a temp folder and can be deleted. Other uses for HTML files are help files, which if deleted, you may not view the help file of the program. Therefore before deleting HTML files, check the folder from where you will delete the files. If they are from a program file, it is not recommended to delete the files, if they are from the internet temporary folder, you can either delete the files manually or you can delete them from the internet explorer by pressing on Delete Browsing History found in Tools.
If you're referring to .exe and .dmg files, try downloading the correct version (windows only accepts .exe and Mac only accepts .dmg
No, rebooting does not delete your files.
All of them! Who needs an operating system, right? Go ahead and delete every last file on your computer!
Any temporary files that World of Warcraft needs are automatically recreated the next time you start the game and login. It should be safe to delete them. The files in WTF, Cache and the interface folders are safe to delete (make sure you make a backup copy should you need them). These folders and any files that are needed will be recreated automatically when you login.
No. There is no problem in deleting zip files. They are just left behind after file downloads. .zip files are compressed archives, containing 1 or more files. Deleting a .zip file will not harm your computer, as they are not system files. If you delete a .zip file, all you will lose is the files contained within. If you have already extracted the files, or if you no longer need them, they are perfectly safe to delete.
Often temporary files does not make any critical harm when deleted. But many programs create temporary files while a project is open etc. It's not allways safe to delete all temporary files. When deleting anything in a operating system you should be sure you know what you are doing.