=====  Form Factors  =====

**SIMM** (Single Inline Memory Module)
  * 30 pin - 8 bit data width
  * 72 pin - 32 bit data width
  * Outdated

**DIMM** (Dual Inline Memory Module)
  * 133mm x 38mm (Approx. 5 1/4 x 1 1/2 inches)
  * 64 bit data width
  * Package used for:
    * SDRAM - 168 pins
    * DDR RAM - 184 pins
    * DDR2 RAM - 240 pins

**RIMM** (Rambus Inline Memory Module) 
  * Desktop version - 184 pins 
  * Laptop Version - 160 pins

**SO-DIMM** (Small Outline DIMM)
  * 68mm x 32mm (Approx. 2 11/16 x 1 1/4 inches)
  * Primary use in laptops
  * 72, 144, and 200 pins

**Micro-DIMM**
  * 45mm x 30mm (Approx. 1 3/4 x 1 3/8 inches)
  * 64 bit data width
  * Primary use in laptops
  * 144 and 172 pins