MEMORY

1. SECONDARY

1.1. external

1.2. non-volatile

1.3. types

1.3.1. magnetic disk

1.3.1.1. floppy disks

1.3.1.2. hard disks

1.3.2. flash memory

1.3.3. optical disks

1.3.3.1. CD

1.3.3.2. DVD

1.3.3.3. Blue Ray

1.3.4. USB drives

1.3.5. magnetic tapes

2. PRIMARY

2.1. RAM

2.1.1. temporary

2.1.2. volatile

2.2. ROM

2.2.1. permanent

2.2.2. non-volatile