For decades, users have bought memory chips to upgrade the RAM memory for their laptops and PC computers. Today the most popular form factor is DIMM or Dual Inline Memory Module.
Traditionally, memory chips were upgraded in sets of two, but now it doesn't really matter if you upgrade just one stick. After you remove the cover over the memory slots, you may need to tilt the memory chip up at a 45 degree angle in order to remove it from the stabilizing clips. Then insert the new memory module firmly into the clips, tilt the memory down until it's flat, replace the cover then power up your computer. Your operating system, such as Mac OS or Windows, should detect the additional memory at boot time. Third party programs exist to take a closer look at your RAM memory.
DRAM memory used for main memory in PCs is volatile meaning it does not store data when the power is off.
TIP: Shop around! Computer memory is a dynamic business, so vendors often do their best to manage inventory as new chips come out. So shop around to find great deals that pop up. A little homework can really pay off!