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.........................../
........................../
__________1/2___________}Exterior
......................3/4
......................./........................}Interior
________5 /6_____________
...................7/8........................}Exterior
..................../
.................../

These angles are always congruent:

Corresponding Angles:
<'s 1 and 5
<'s 2 and 6
<'s 3 and 7
<'s 4 and 8

Alternate Exterior Angles:
<'s 1 and 8
<'s 2 and 7

Alternate Interior Angles:
<'s 3 and 6
<'s 4 and 5

These angles are always Supplementary [x+y=180]:

Same Side Interior Angles:
<'s 3 and 5
<'s 4 and 6