Technical question about the forum symbols

I know if there is a star in the little picture next to the topic, it means I have wrote in it. But why are some topics having blue balls next to them, and some red? What is the difference? And why are the lines inside those balls sometimes moving, and in some they stay still? I didn't find any explanation on what they try to symbolize with movement or color..

The blue ball with lines is just the 'default' symbol for a 'topic'.

When the lines are moving, it means it's a 'busy topic' cos there's lots of lines.

Oh and I think the red one means there's "unread" posts, like new posts since last time you were here.

V2

Oh, OK. Thanks a lot, V2.