click below
click below
Normal Size Small Size show me how
DAVJ277 1.2.2
J277 GCSE CS 1.2.2 Secondary Storage
Question | Answer |
---|---|
Secondary storage—What is it and why do we need it? | Long term/non-volatile storage of data and files We use it for the permanent/semi-permanent storage of files. Secondary storage is needed to store the operating system (and other applications and files) even when the system is switched off. |
Secondary storage technologies—What are the three types? | Optical Magnetic Solid state |
What are the characteristics of different types of secondary storage that you need to consider for suitability? | Capacity Speed Portability Durability Reliability Cost |
How many 4MB pictures can be stored on a 16GB memory stick? | 16,000,000,000 divided by 4,000,000 = 4,000 pictures. |
How much capacity would be required to store a 5,000 character word processed document using ASCII? | 5,000 bytes (1 byte per character) or 5 kilobytes |
Why does a digital camera need secondary storage? | For long term/non-volatile storage/store photos when device is turned off To store photos EXAM TIP! Refer to context of question |
Optical storage—give examples of devices that use this and characteristics | CD/R, CD/RW, DVD/R, DVD/RW Use: music, films and archive files. Low capacity. Slow access speed. High portability. Prone to scratches. Low cost—suitable if multiple copies needed. |
Magnetic storage—give examples of devices that use this and characteristics | Eg. Hard disk drive. High capacity for low cost. Medium data access speed. Low portability (moving parts). Reliable but not durable . Medium cost. |
Solid state storage—give examples of devices that use this and characteristics | Memory cards & solid state hard drive (SSD). Use: digital cameras and smartphones—any portable device Medium capacity. High portability. Reliable and durable. No moving parts. Fast data access speed. High cost. |
Secondary storage technology most suitable for: 1. Skiing headcam 2. Video library 3. Free gift for a magazine 4. Portable games console 5. Engine management system | Skiing headcame - Solid state: durable, no moving parts medium capacity (or high but expensive). Video library - Magnetic: high capacity relatively cheap. Free gift for magazine - Optical: low cost for multiple copies. Portable games console - Solid state: medium capacity, portable. Engine managment system - Solid state: durable. fast. no moving parts |