Digital Scope, why is my line jittery ?

[apples]

Just wondering why the yellow line on my digital scope (RIGOL DS1052E) is not a dead flat still line. The top off it looks like it has a graphic equalizer going on. It is only about 1/2 the height of the thickness of the line but is it supposed to be jittery like that?

 

[(*steve*)]

That's noise, and yes, it's normal.