How to create simple animation with transparent background? I'd like to create basically a HUD (head up display) using simple animations.  The following are three different videos:


animated checkmark
animated circle
animated underline


Each video just draws out the symbol.  I'd like transparent backgrounds so these small videos can be used in other videos for effects.

As an example, in some video, I can introduce the animated checkmark.  You'll see the checkmark next to something I want to emphasize but everything under the checkmark (in the host video) is still visible (because of transparency in the checkmark video).

How can this be done in AE?  I'm not sure how to create a checkmark that basically draws itself out.  Are there any tutorials (youtube) that show something like this?
All of the animations you want to do there are achievable with masks and the Stroke effect.

I suggest you start to generally learn to use After Effects, these are very simple things you want to do there and you shouldn't need any tutorial once you understand the very basics of After Effects.