This depends on the programs. Most programs will situate their contents in multiple locations, so if it's on your computer, you'll need to know where all of a program is stored. It can be easier to download the program from scratch again as it brings in all of the needed content for you. If you are trying to transfer from a computer, at the very least be sure to capture the EXE, Application and Java files; however, there are usually many other files too. Also, the programs will differ between operating systems (for example, EXE is Windows, while .app is Mac). End answer: it can be done but it's easier if you can download the program afresh.
Yes you can but if you have a lot of files, a flash drive won't back it all up. If you only need to back up 32GB-64GB for example, you could back it up on the flash drive. However, anything bigger isn't sensible for flash drives; you're better off getting an external hard drive. Also, it's not a long-term storage option––it can corrupt easily or be lost.
It's never been easier to take all the files, data or media you want with you wherever you go. Generally about the size of a stick of gum, a USB flash drive lets you store any file from your computer so you can save it, transport it, and load it onto another computer in seconds. You simply plug the flash drive into your USB port and drag any files you want onto its icon on your desktop. Best of all, flash drives have no internal moving parts, so they're very resistant to breaking by being bumped or dropped.