Chapter 1 (Abigail) Flashcards
(48 cards)
Data
Raw facts and figures with no meaning attached
Information
Data with meaning
Number system of which computers store data
Binary System
Smallest unit of storage, has a value of 0 or 1
Binary digIT (bit)
ASCII meaning
American Standard Code for Information Interchange
Integer Numbers
Numeric data type- a whole number which can be positive or negative
Real Numbers
Numeric data type- includes whole numbers (integers) as well as numbers with decimal and fraction parts.
Long Date
Date/ Time type- Saturday, April 1, 2018
Medium Date
Date/ Time type- 1 Apr 2018
Short Date
Date/ Time type- 01/04/2018
Long time
Date/ Time type- 13:26:34
Medium time
Date/ Time type- 01:26PM
Short time
Date/ Time type- 13:26
What is a character?
A single letter or digit represented by codes from the character set used by the computer (e.g. ASCII)
What is a string?
Textual data in the form of a sequence of characters from a character set. This could be in the form of a word. A string will have a variable number of characters
Arrange in ascending order: a nibble, a megabyte, a byte, a terabyte, a kilobyte, a bit,
A bit, a nibble, a byte, a kilobyte, a megabyte, a gigabyte, a terabyte
What is a pixel?
The smallest unit of a digital image that can be displayed & edited on a computer screen. Each pixel can have its own individual colour and, together, a large group of them can make a complete image.
What is image resolution and how is it represented?
Image resolution describe the quality of an image. The greater the number of pixels used in an image, the higher the image resolution and the sharper the image. However, higher resolution images require more storage space. Image resolution is represented by 2 numbers, e.g. 1280 x 720. The first number is the amount of pixels displayed horizontally while the second is the number of pixels displayed vertically.
What are bitmap graphics?
- Made from a grid of pixels
- E.g photo on a phone or a computer scan
- Higher resolution= Higher quality
- Take up a lot of storage space as bitmap graphics store details about every single element (pixels) of the image
- Can be compressed to reduce file size but this can result in loss of quality.
- Pixelation can occur when the bitmap image is enlarged too much
What are vector graphics?
- Images made from mathematical components, e.g. curves and shapes, instead of pixels
- Components can be edited separately
- Require less storage capacity as they store information about the shape of individual components rather than using pixels.
- Meaning they can be saved as smaller files and edited without a loss of quality when enlarged
- Used for the likes of logos
What is streaming?
A process which allows video to be viewed on a website or all straight away, without having to wait for the full video to be downloaded.
What is a buffer?
An allocated part of memory that is used to store a downloaded part of a video before it is watched. When a user is watching a video, a buffer is used to download the next part.
What is sample rate?
The number of audio sound samples captured every second to represent the sounds digitally & is measured in Hertz (Hz). The more samples taken, the more accurate the sound wave which results in better quality audio.
What is bit depth?
The number of buts used to store each sound sample. Higher quality sound requires more depth.
