these are just examples. don't memorise them all. the main thing to understand is the notation
U -> union / OR.
for example with AUB think about the area of the venn diagram with A and the area of the venn diagram with B -> its all that area that is covered by A OR B OR both.
∩ -> intersection/AND.
For example with A∩B think about the area of A and B again, but this time, because its the intersection/AND, its only the area covered by both A AND B.
line over -> NOT. Whatever parts the line is over is NOT
For example notA is everything thats not A. If you take the area shaded by A then invert it so everything shaded becomes unshaded and everything unshaded becomes shaded. Thats NOT
then we can combine these. like your notA∩B
Consider the areas of the venn diagram that are NOT shaded by A, and the areas that are shaded by B. What parts are shaded by both of these two areas? That's what notA∩B means.