It's called an "animated gif", an image format that allows multiple images to be store as one file.
Scratch Wiki Article
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If you saw mine (it might change if u read this in the future) it says at the bottom that it's made with bannermaker.com You can add sparkleys!
when gf clicked repeat until <(timer) > [10]> go to [mouse-pointer v] end think [Scripts in your posts!] for (3) secs
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