you should probably keep them in a binder suitcase or makes 5 copies and put 2 of them in a file cabinet
Backup
A "Full Backup".
Yes if you have copied and thus created a backup on your flash drive it is safe to delete them off your computer, but I would recommend keeping them there so you have two copies of them in case something happens to on of the copies.
Totally depends on the backup methodology and the rotation scheme. I have a couple of clients that backup everything everyday and keep the tapes for two weeks. They have 14 copies. Other's backup everything (or changed data in some cases) everyday, and keep the daily copies for two weeks, but keep the weekly tapes for months. There could be 30-40 copies in those cases.
backup
backup
To supply a backup in case the original is destroyed.
Yes, ordinary backup utilities (including those built into OSs like Windows and Mac OS X) do this automatically. You can also manually backup your files. What you cannot do within the usual licence rules is create copies to install on additional computers as runnable applications. Backup copies are fine.
micronucleus
A system backup. This typically copies key operating system files and programs, but not user data.
Because it copies files which you want to backup and creates a special king of archive. So if you want to backup 500 Mb you will get the archive file 500 Mb.
It allows you to play "backup" or copies of games but can get you banned for Xbox live if caught.