1. GCSE COMPUTER SCIENCE
Topic 3 - Data
3.8 Data Storage

2. Speed Units Speed units are needed to measure how fast processors are.
Example A 1GHz processor can compute 1 billion instructions a second.
The faster a CPU is, the more computations it can perform a second.

3. The base unit of speed is called a:
Speed Units
The base unit of speed is called a:
Hertz

4. The next unit of speed is:
Speed Units
The next unit of speed is:
Kilohertz
1 Kilohertz is 1024 Hertz

5. Megahertz Speed Speed Units The next unit of speed is:
1 Megahertz is 1024 Kilohertz

6. Gigahertz Speed Speed Units The final unit of speed is:
1 Gigahertz is 1024 Megahertz

7. Storage Units
Storage units are needed measure how much data a device can hold.
Example A 1GB USB stick can hold roughly 230 mp3s, 16 hours of music or 20 music albums. Not enough to hold a movie.
The larger a storage device is, the more data is can hold.

8. Half a byte (4 bits) is called a nibble
Storage
Storage Units
The base unit of storage is called a:
Byte
There are 8 bits in a byte
Half a byte (4 bits) is called a nibble

9. The next unit of storage is:
Storage Units
The next unit of storage is:
Kilobytes
1 Kilobytes is 1024 Bytes

10. The next unit of storage is:
Storage Units
The next unit of storage is:
Megabytes
1 Megabyte is 1024 Kilobytes

11. The next unit of storage is:
Storage Units
The next unit of storage is:
Gigabytes
1 Gigabyte is 1024 Megabytes

12. The final unit of storage is:
Storage Units
The final unit of storage is:
Terabytes
1 Terabyte is 1024 Gigabytes

13. You need to remember these, especially the order.
Speed & Storage Units: Recap
Speed Units
Hertz (Hz)
Storage Units
bit (b)
Hertz
Kilohertz (KHz)
Bytes
Byte (B)
Megahertz (MHz)
Kilobyte (KB)
Gigahertz(GHz)
Megabyte (MB)
Gigabyte (GB)
Terabyte (TB)
You need to remember these, especially the order.
ACTIVITY
Write these down in your books under a title of speed and storage units

14. Convert the following values into Bytes:
Storage Unit Conversions
Convert the following values into Bytes:
Value
Bytes
100 Nibbles 50
1 Kilobyte
1024
150 Kilobytes
150 * 1024
1 Megabyte
1024 * 1024
10 Megabytes
10 * (1024 * 1024)
5 Gigabytes
5 * (1024 * 1024* 1024)
2 Terabytes
2* (1024 * 1024 * 1024* 1024)

15. Which of the following is the largest?
Storage Units: Quiz
Which of the following is the largest?
1/5
100 Kilobytes or
100 Megabytes
100 Megabytes

16. Which of the following is the largest?
Storage Units: Quiz
Which of the following is the largest?
2/5
1000 Bytes or
1 Kilobyte
1 Kilobyte

17. Which of the following is the largest?
Storage Units: Quiz
Which of the following is the largest?
3/5
2500 Gigabytes or
250 Terabytes
250 Terabytes

18. Which of the following is the largest?
Storage Units: Quiz
Which of the following is the largest?
4/5
10,000,000 Bytes or
8 Megabytes
10,000,000 Bytes

19. Which of the following is the largest?
Storage Units: Quiz
Which of the following is the largest?
5/5
1 Terabyte or
500 Gigabytes
1 Terabyte

20. Media Storage Music 3-4 min 128kbps MP3 40,000 3-4 min 320kbps MP3
16,000
3-4 min FLAC
6,500
3-4 min WAV
4000
Apple iPhone XR 128GB
Please note these are approximate values

21. Media Storage Photos 8MP JPEG 45,000 12MP JPEG 30,000 12MP RAW 3,000
1,500
Apple iPhone XR 128GB
Please note these are approximate values

22. Media Storage Video 480p Low Definition > 20 hours
720p Standard Definition (SD)
> 10 hours
1080p High Definition (HD)
< 5 hours
4k Ultra High Definition (UHD)
< 30 mins
Apple iPhone XR 128GB
Please note these are approximate values

23. Apps (Mobile Applications)
Media Storage
Apps (Mobile Applications)
Standard Apps
Games
200
Apple iPhone XR 128GB
Please note these are approximate values

24. Media Storage Documents Presentations 10,000 Word Processor 700,000
Spreadsheets
200,000
Novels
400,000
Apple iPhone XR 128GB
Please note these are approximate values