Summary 📝

Computers use number systems to store and process data. While we use base 10 (decimal), computers use base 2 (binary) because they work using two states: on and off. Each binary digit (bit) is either a 0 or 1. Understanding binary is important for understanding how computers count, store numbers, and perform calculations. Binary numbers can be converted to and from decimal numbers by using place values. Another useful base is hexadecimal (base 16), which is shorter than binary and easier for humans to read. In hexadecimal, digits go from 0–9 and then A–F to represent 10–15. Knowing how to convert between binary, decimal, and hexadecimal is an essential computer science skill. These conversions help programmers and technicians understand data storage, memory addresses, and colour codes in computer systems. 

Key learning Points 📌

• Decimal (base 10): The number system we use every day, using digits 0–9.
  Binary (base 2): Used by computers; only uses 0s and 1s.

• Each binary place value is a power of 2 (1, 2, 4, 8, 16, etc.).

• To convert binary to decimal, add up the place values where there's a 1.

• Hexadecimal (base 16): Easier to read than binary; uses 0–9 and A–F.

• A = 10, B = 11, ..., F = 15.

• Used for things like colour codes, memory addresses, and machine code.

• Convert between binary and hexadecimal by grouping binary digits in sets of four.

• Learning these conversions helps understand how data is handled in systems.