1. Memory
Data are stored here temporarily. Most memory is volatile: when power is lost, data that's stored in memory is lost.
Most modern computer memory consists of semiconductors on chips. Each chip is packaged in a dual in-line package (DIP).
Each DIP is soldered to a memory module or "stick". 
Memory sticks contain 8, 9, or more DIPs and plug into connectors on the computer motherboard.
Memory consists of millions of cells, with one bit per cell. Each cell contains either a 1 (One) or a 0 (Zero). RAM (random access memory) is called that because the CPU can randomly access any cell, without reading through any other cells first.
Memory cells are arranged in a logical matrix of rows and columns. Each cell resides at a unique address that consists of the intersection of a row and a column.
The CPU (central processing unit) has direct access to every cell in memory.