what does ctrl-a do in (vertex) edit mode actually do

Support Basics & Interface
1

I was looking at this tutorial for use of the skin modifier.

He uses shortcut ctrl-A to change the size of the thickness of the skin but what does that Shortcut actually set? I can’t find it anywhere in the menu’s. I wonder whet other sues this shortcut has with other modifiers?

Many thanks

2

With the skin modifier it changes the skin radius

See the manual
https://www.blender.org/manual/modeling/modifiers/generate/skin.html
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.64/Skin_Modifier

3

So it doesn’t do anything else? I found it is named scale vertex…

I was wondering if it is used by any other features in blender

4

If you look in the input settings and search for ctrl a with filter method changed from name to key-binding you can see what commands have ctrl a (and other modifiers) as the input. For the 3d view (edit mode) it seems like the skin modifier thing is the only one.