fastball- basic pitch. can either run, dive, rise or be flat. changeup- off speed pitch. usually dives and runs slightly. 10-15 mph slower than fastball. Curve- most effective curve drops straight down at a 12 to 6 angle. variations like a slurve go from 2 to 8 (right handed pitcher) or from 10 to 4 (left handed pitcher) Slider- nasty pitch. needs to be thrown hard. 5-7 mph slower than fastball. has a dropping and sliding action to it. splitfinger- variation of changeup. extremely dirty when thrown correctly. drops straight down and is usually 5-7 mph slower than fastball. very sudden drop to it. the above are the most common that most pitchers in the majors and college will use. I pitched for 2 years in college and they were the most effective. below is a list of more, uncommon pitches. Fork Ball- just like the splitfinger but slower. Knuckleball- doesn' rotate which gives it a great bit of random movement. however, you sacrifice velocity greatly. Eephus pitch- this is a hilarious pitch in which the pitcher winds up and throws like he is throwing a fastball as hard as he possibly can, but right at the end slows his arm down and lobs the ball veryslowly.

Uno Mas - thought this went as a comment: You may be too young - but how do you describe a "drop" pitch?