Hallo Bielefelder,
also die Videos kannst Du kostenlos so oft ansehen wie Du möchtest. Damit man nicht immer seine liebsten Videos suchen muss, kann man seine Favoriten sammeln. Herunterladen kann man die Videos leider nicht. Es gibt allerdings ein Programm, mit dem man das aufnehmen kann, was der Rechner gerade abspielt und dann als Audiodatei speichern kann. Das hab ich leider auch nicht - vielleicht kann hier jemand anders helfen?!
Ansonsten hab ich Dir einfach mal den Orginaltext von YouTube bezüglich Deiner Frage kopiert (hoffe das hilft erstmal etwas...
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Can I download videos to watch later?
No. YouTube's video player is designed to be used within your browser as an Internet experience; that's why we have comments and other community features attached to the videos. If you'd like to temporarily save videos to watch later, you can add them to your QuickList, and if you'd like to save them more permanently, login and click "Save to Favorites" under the videos you'd like to keep.
How do I watch and save videos?
Watching videos on YouTube couldn't be easier—just come to the site and browse around, or search for subjects that interest you. To save videos for later, you need to sign up as a member, and then click the 'Add to Favorites' link underneath the videos you want to watch later. You can also use the QuickList feaaature or create playlists to group videos together into your own personal categories.
What is a QuickList and how do I use it?
QuickList is a way to make a list of videos to watch later. To add videos to your list, just click the "+" on any video you'd like to save. Once your list is created, you can see the QuickList bar under any video you watch. Click the down arrow to display the full bar, and you can skip around in your list or just click "Play All" to watch them all in sequence. If you haven't made one yet, you can look at the tutorial.
How do I clear my search history on YouTube?
YouTube doesn't save your searches, but your browser probably does. If you don't want to see your previous search terms displayed in the search field, you need to clear the search history in your browser