Getting to know

Storage Media1. Stores information

2. Retrieve information for later use

The Diskette is a magnetic storageStorage Space/Size/Capacity = 1.44 MB

Write Protect tabRead onlyOrRead and write

The Zip Disk uses magnetic material too!

Storage Space/Size/Capacity = 250 MB

The Hard DiskStorage Space/Size/Capacity = 160 / 320 / 500 GB

Or even 1GB!

The CD-ROMStorage Space/Size/Capacity = 700 MB

The DVDStorage Space/Size/Capacity = 4.7GB

http://electronics.howstuffworks.com/cd.htm

The USB Flash Memory/ Thumbdrive

Storage Space/Size/Capacity = 2 or 4 GB

Units to Measure Computer Data

• The smallest unit for data is Bit.

• 1 Bit stores only 2 values

• 2 values “1” or “0”

• It is called the Binary Code

http://computer.howstuffworks.com/

More Units

• Bit (b)• Byte (B)• Kilobyte (kB)• Megabyte (MB)• Gigabyte (GB)

Unit Size

1B 8 b

kB 1024 B

1 MB 1024 kB

1 GB 1024 MBBIG UNIT

x x

x

X

SMALL UNIT

More Programs Running, More Main Memory?

• Demonstration for use of CPU and use of main memory.

• The amount of memory used by a program increases with the program’s activity

• The amount of memory used increases with more programs being opened.

• The CPU’s usage increases for a while before it drops. Then the memory usage increases.