Data & representation · Both
Binary & Data Representation
Computers store everything as binary. You need to convert between bases and understand units of storage.
Binary and denary
Binary (base 2) uses 0 and 1.
Place values: … 128 64 32 16 8 4 2 1
Add the place values where there is a 1 to convert to denary.
Worked example
Convert 01001101 to denary.
Solution: 64+8+4+1 = **77**
Units and characters
• Bit → nibble (4) → byte (8) → KB → MB → GB → TB
• Characters: ASCII / Unicode map numbers to symbols
• Hex (base 16) is a shorter way to write binary
Practice questions
1. How many bits in a byte?
2. What is binary place value of the leftmost bit in an 8-bit number?