.Something --> class="something" (can occur multiple times) #Something --> id="something" (should be unique per page)
So in other words a declaration like .thrColFix #sidebar1 {
float: left;
width: 240px;
height: 570px;
}
sets the given attributes of the one element which has an id of "sidebar" and resides inside any element that has the class ".thrColFix".
Who is the sepples faggot that keeps shitting up wikipedia articles with their ``example code"? Enough! No one is impressed with your terrible language and it doesn't illuminate any article.