RAM

• RAM, or random access memory, is the memory your computer uses to run software. This is not your overall storage, just the memory needed to run programs, such as Windows or Firefox.
  
  

DDR2 RAM

• DDR SDRAM stands for double data rate synchronous dynamic random access memory. DDR RAM is twice as fast as the older SDRAM, and DDR2 RAM is four times faster.
  
  

PC2-8500

• 8500 refers to the rate of data transfer. In other words, this type of DDR2 RAM has a maximum rate of 8500 megabytes (MB) per second. This is the maximum rate for DDR2 RAM based on a maximum bus speed of 266 MHz.
  
  

240-Pin

• 240-pin refers to the number of pins or gold metal strips located on the connecting side of the RAM. 240-pin RAM is for use in desktop computers, and is not compatible with laptop or netbook computers.