The F in GIF stands for Format. And for many years this meant the data format.
0000000: 4749 4638 3961 a000 5000 e7ff 0064 7082 GIF89a..P....dp.
0000010: 6770 7d66 6f99 6d6f 8f67 7284 6a71 8a64 gp}fo.mo.gr.jq.d
[…]
0000320: 21fe 1f43 7265 6174 6564 2062 7920 5374 !..Created by St
0000330: 6566 616e 2053 6368 6f6c 6c20 2d2d 2043 efan Scholl -- C
0000340: 4330 0021 f904 090a 00ff 002c 0000 0000 C0.!.......,....
[…]Today every short video file without audio is called a GIF. Regardless of the data format.