Paper Patched Flat Nose  Lead bullet with paper patching that functions as lubrication and as a gas seal. Also reduces the leading of a barrel. Was an early, but a very effective method.  Paper Patched Bullets had no cannelures.          
The flat nose was often used in lever action guns to avoid bullets in the tube from directly hitting the next bullets primer. Lead.

Paper Patched Round  Nose  Lead bullet with paper patching that functions as lubrication and as a gas seal. Also reduces the leading of a barrel. Was an early, but a very effective method.  Paper Patched Bullets had no cannelures.          
The flat nose was often used in lever action guns to avoid bullets in the tube from directly hitting the next bullets primer. Lead.

Outside Lubricated Flat Nose

Grooves for lubrication, Can be wax, Fat etc. The Flat Nose was often used inlever action rifles to avoid bullets in the tube from hitting the other bullets primer.

Outside Lubricated Round Nose

Lead, Lubrication method same as the Flat Nose. 

Outside Lubricated Pointed Nose Lead, Lubrication method same as the Flat Nose. 

Mauser Style Long Nose.

Long bullet, usually cased in Nickle, Brass,
Copper or even steel.
The long bullet was to
increase weight of bullet
with small calibers, thus
trying to attempt a bigger
impact on the target.

Truncated 

Common in many modern pistols. Often found in Hollow Point Form. Copper, Nickel or Brass Plating.

  Pointed (Sabre Tip)

One of the more accurate rifle
 bullets. Jacketed and often tipped
with lead or plastic to increase
expansion on impact.

Round Nose

Copper, Nickle or Brass Jackets over lead core. Commin in Pistol cartridges.

   Ball     

Usually always a "lead" Ball.

Cannelevered Round Nose

Lead or Jacketed Lead.

Round Nose Hollow point    

Jacketed lead. Hollow Point causes "Mushrooming" upon impact for a larger hole.

Jacketed Flat Nose 

Same basic concept as Paper patched Jacketed only these more modern rounds utilize brass, copper or Nickel to jacket the bullet. 

 Jacketed Round Nose (Kling Kor)

Copper or Nickel cased with lead tip for maximum expansion. Some bullets feature a metal insert to shatter the lead upon impact.

Wadcutter

Jacketed or Plain lead.

Hoxie

Hoxie Bullets used a metal ball at
the end, hoping to cause significant
fragmentation and expansion upon impact.