GIF
https://en.wikipedia.org/wiki/GIF (Links to an external site.)Links to an external site.

High Efficiency Image File Format
https://en.wikipedia.org/wiki/High_Efficiency_Image_File_Format (Links to an external site.)Links to an external site.

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 (Links to an external site.)Links to an external site.

Animated GIFs

 (Links to an external site.)Links to an external site.

PBS Special | 6m 55s

https://www.pbs.org/video/-off-book-animated-gifs/ (Links to an external site.)Links to an external site.

Animated GIF in Photoshop Production Resources

Adobe - How to make an Animated GIF
https://helpx.adobe.com/photoshop/how-to/make-animated-gif.html (Links to an external site.)Links to an external site.

Created Frame based Animations
https://helpx.adobe.com/photoshop/using/creating-frame-animations.html (Links to an external site.)Links to an external site.

Saving in GIF format
https://helpx.adobe.com/photoshop/using/saving-files-graphics-formats.html#save_in_gif_format (Links to an external site.)Links to an external site.

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Video tutorials:

Transforming Layers over time (Links to an external site.)Links to an external site.. Julieanne Kost (3:52)

Creating masks to move over time (Links to an external site.)Links to an external site.. Julieanne Kost (3:17)

Create animations with audio (Links to an external site.)Links to an external site.. Tutorial article by Rafiq Elmansy.

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Timeline Animations Vs Frame based Animation - VIDEO Editing

Video and Animation Overview in Photoshop

https://helpx.adobe.com/photoshop/using/video-animation-overview.html (Links to an external site.)Links to an external site.

Creating Timeline based Animations

https://helpx.adobe.com/photoshop/using/creating-timeline-animations.html (Links to an external site.)Links to an external site.

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Video Editing Features in Photoshop

https://helpx.adobe.com/photoshop/using/new-video-features-photoshop-cs6.html (Links to an external site.)Links to an external site.

Video tutorials:

Intuitive video Workflow (Links to an external site.)Links to an external site.: How to add video clips, trim video clips, add a music track, and render your movie for playback by your audience. By RC Conception (8:18)

How to edit video in Photoshop (Links to an external site.)Links to an external site.
. By Matthew Gore (10:42)

Slip editing (Links to an external site.)Links to an external site.
 to adjust the in and out points of a video without changing the clip duration. By Meredith Payne-Stotzner (1:20)

Frame skipping and caching (Links to an external site.)Links to an external site.
 to improve playback performance. By Meredith Payne-Stotzner (2:07)

Changing clip speed: Slow and Fast Motion. (Links to an external site.)Links to an external site. By Jeff Sengstack (9:45). How to put clips into slow motion or speed them up. By Jeff Sengstack (9:45)