What are the important latitudes?

The important parallels of latitudes are:

• The equator (0°)
• The North Pole (90°N) 
• The South Pole (90° S)
• Tropic of Cancer (23½° N) in the Northern Hemisphere. 
• Tropic of Capricorn (23½° S) in the Southern Hemisphere. 
• Arctic Circle at 66½° north of the equator. 
• Antarctic Circle at 66½° south of the equator.

Further Reading:

• GLOBE: LATITUDES AND LONGITUDES
• Geography Notes