What is this ? and my guess

[html20009876]

Hi friends,
I can not find answer in google ...

Newbie questions about css formats:

1. #myMenu ul li a {....}
2. #myMenu, #myMenu ul {...}

3. #myMenu > li > a {...}
4. #myMenu ul li:hover a {...}

I guess that:
1 stands for "a of li of ul of #myMenu"
2 stands for "#myMenu and ul of #myMenu".

I totally don't know what 3 and 4 stand for.

Please help and explain.

Thanks.

.

[legend@12]

the third one stand for "#myMenu which immediately follows <li> and immediately follows <a> tag"
The fourth one stand for "In #myMenu, in <ul> when mouse hover over <li> the stylesheet is applied to <a>"

[html20009876]

Hi legend,
Thanks.

As my understanding,
#myMenu > li > a {...} has higher priorities than #myMenu li a {...}
Or
#myMenu > li > a {...} overwrites #myMenu li a {...}

Is it correct?