Zusammenfassung der Ressource
Units, Numbers and
Characters - Computing
- UNITS
- BIT - smallest unit of data, represented as a
binary number, either 1 (true) or 0 (false)
- BYTE - contains 8 bits, one keyboard
character takes up 1 byte of storage
- NIBBLE - 4 bits, 2 make a byte, less common
- KILOBYTE - unit of storage capacity, 1024 bytes
(or 1000), equivalent to 1024 characters on screen
- The more detailed an image, the
more kilobytes of storage it takes up
- MEGABYTE - unit of storage capacity, 1,048,576 bytes
or 1,024 kilobytes (or 1 million bytes/1000 kilobytes)
- A typical MP3 song can be anywhere
between 3 to 5 megabytes in size and a CD
can store up to 650 megabytes of data.
- GIGABYTE - 1024 megabytes, a DVD can
store a film around 4-8 gigabytes and hard
disks can hold typically 160+ gigabytes
- TERABYTE - 1024 gigabytes,
can store huge amounts of data
- ANALOGUE DATA - on a continuous
scale, used in the real world
- Computers can only deal with digital
data (0 or 1). Analogue data must be
converted to digital using an ADC
- NUMBERS
- Denary number system:
0, 1, 2, 3, 4, 5, 6, 7, 8, 9
- 'Base 10' number system
- Multiply each digit on the left by a progressive factor of 10 in
order to calculate its value e.g. '123' = 3 + (10 * 2) + (100 * 1)
- Binary: 0 or 1
- 'Base 2' number system
- Multiply each digit on the left by a
progressive factor of 2 e.g. '37' =
00100101 (1 * 1) + (2 * 0) + (4 * 1)
+ (8 * 0) + (16 * 0) + (32 * 1) = 37