I was wondering, if you have any basic rule whether to use a symbol, e.g.
+, just plain or in a circle, e.g.
(+). One example is the star
(★) to favorite this very question (on the left hand side), it is circled. Whereas the star in Chrome to favorite a website is not circled.
Is there a different meaning or perception behind it?
For myself, for example for arrows, I could think of circled means action (go, next, etc) and plain means navigation (scroll, move right, etc).
When do you use circled symbols?