1. Types of Gears Spur Gears Known as the common gear. Strong
Easy to manufacture
Cost effective
Makes noise under curtain types of load.
Common use: Industrial applications where gear noise is not a concern.

2. Types of Gears Helical Strong Moderate difficulty in manufacturing.
Reduced noise at higher revelation speeds.
Common use: Manual transmission in an automobile.

3. Types of Gears Herringbone AKA: Double Helical
Very difficult to manufacture
Expensive
Does not require a thrust bearing. Side load is pushed to the center of the gear and does not allow for gear misalignment.
Very smooth
Common use: Large displacement pumps

4. Types of Gears Spur Bevel Same rules as a common spur gear.
Used when an output shaft location requires offset location.
Often 90 degrees of separation from input shaft to output shaft. Other degrees of separation are possible with a change in gear geometry.
Common use: Roll up doors and angle grinders.

5. Types of Gears Spiral Bevel Similar to the Spur Bevel gear.
Used when a smother and quieter application is required.
Difficult to manufacture
High strength
Bevel gears of equal size are often known as Miter gears.
Hypoid gears are arranged with the pinion above or below the ring gear centerline. Thus allowing for bigger and stronger pinion gears.
Common use: Differential in an automobile.

6. Types of Gears
Worm
Used when an output shaft location requires offset location and additional gear reduction is required.
Advanced manufacturing
Input and output are not interchangeable.
Considered to be a self locking.
Common use: Conveyer belts, presses and other industrial machinery.

7. Types of Gears Rack and Pinion Moderate strength
Less difficult to manufacture.
Used to convert rotational motion to linear motion.
Lesser mechanical advantage
Reduced gear backlash offers great feel if manually controlled by a human.
Common use: Steering mechanism in automobile

8. Types of Gears Planetary Very strong Advanced manufacturing
Light weight
Very low noise
Can be stacked for additional gear reduction.
Can be manipulated to create a reverse direction output.
Common use: Shifting transmissions on power drills and automobiles.