Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
30 Cards in this Set
- Front
- Back
|
What are the three types of storage |
Optical, solid state, magnetic |
|
|
What is secondary storage (3) |
- Non volatile storage - external to the computer - used for long term storage |
|
|
How do magnetic devices work |
Use magnetic fields to (de)magnetise tiny individual sections of a metal spinning desk. Each section represents 1 bit |
|
|
What are some features of magnetic devices (6) |
- Fairly cheap - High in capacity - High in durability - Vulnerable to damage when dropped due to moving parts - Strong magnets can erase data - Not portable |
|
|
How do optic devices work |
Uses a laser to scan the surface of the device. The surface is divided into tracks with lands and pits. Lands reflect the laser, while pits scatter it, representing 1 and 0. A sensor looks for the reflected light |
|
|
Features of optical storage (5) |
- Very cheap - Portable - Won't be damaged by water or shocks - Can get scratched easily - Slow access times |
|
|
What can optical storage be as? (3) |
- CDs - DVDs - Blu-ray |
|
|
How do solid state devices work |
They use non volatile ram |
|
|
What are some features of solid state drives (6) |
- Faster access times - Smaller capacity - Expensive - Portable - Number of times it can be written to is limited |
|
|
Smallest to biggest binary units (8) |
bit, nibble, byte, kilobyte, megabyte, gigabyte, terabyte, petabyte |
|
|
What is analogue data |
A real life signal |
|
|
How can analogue data be used by a computer |
It's converted to digital data by converting it to binary data |
|
|
What is a character set |
A table that links a character to a number. This allows the computer system to convert text into binary |
|
|
What are the 2 standard character sets |
ASCII and Unicode |
|
|
What is the character set of extended ASCII |
256 |
|
|
How many bits does Unicode use, and what is it's character set |
16 bits. 65000 |
|
|
What is a pixel and what does it stand for |
Picture element - a single dot of colour on a screen |
|
|
What is colour depth? How does it increase the file size? |
- The number of bits used for each pixel. - A higher colour depth his increases file size |
|
|
How to calculate image size |
width x height |
|
|
How do you calculate image file size |
height * width* colour depth |
|
|
What is resolution |
The fineness of detail that can be seen in an image |
|
|
What is metadata in an image file? What are some examples (3) |
Metadata is information about the image data, such as size of the image, resolution, colour depth |
|
|
What is a sample? |
A digitally recorded fragment of sound taken from an existing track |
|
|
What is the sample rate? What's it measured in? |
the number of samples that are taken per second. It's measured in hz |
|
|
What is bit depth in sound storage? |
The amount of bits available to store each sample |
|
|
What is the sample rate? |
the measure of how much data is processed for each second |
|
|
What are the 2 types of compression |
Lossy and lossless |
|
|
What is compression |
Altering the data in a file to reduce the file size |
|
|
What is lossy compression? What could it be used for? (2) |
When data is permanently removed to reduce the file size. This could be used for images and audio files where all the data isn't necessary to have |
|
|
What is lossless compression? What could this be used for? |
Reducing the file size without losing any data. This could be used for documents where all the data necessary to have |
