Computer science

Computational Thinking

A problem-solving process that formulates a problem so a computer can solve it.

Decomposition

Breaking a complex problem down into smaller, more manageable parts.

Abstraction

Removing unnecessary details from a problem to focus only on the essential characteristics.

Pattern Recognition

Identifying similarities or trends within problems to find efficient solutions.

Algorithmic Thinking

Developing a step-by-step set of rules or instructions to solve a problem.

Flowchart

A visual diagram that shows the step-by-step progression of an algorithm.

Terminal (Oval)

Symbol representing the Start or End of an algorithm.

Process (Rectangle)

Symbol representing an action, calculation, or variable assignment.

Input / Output (Parallelogram)

Symbol representing data entered into the system or displayed to the user.

Decision (Diamond)

Symbol representing a question with a Yes/No or True/False outcome that splits the program path.

Subroutine (Rectangle with double vertical borders)

Symbol representing a call to a pre-defined procedure or function.

Bit

A single binary digit, either 0 or 1, and the smallest unit of data.

Byte

A group of 8 bits.

Binary (Base-2)

A number system that uses only two digits: 0 and 1.

Binary

A number system that uses only two digits: 0 and 1.

Denary / Decimal

The standard human number system using digits 0-9.

Hexadecimal

A number system using 16 digits (0-9 and A-F, where A=10, B=11, C=12, D=13, E=14, F=15).

Binary Shift

Moving bits left or right to multiply or divide.

Left Shift

Multiplies a number by 2 for every place shifted.

Right Shift

Divides a number by 2 for every place shifted (truncating any fractions).

Overflow Error

Occurs when the result of a binary calculation requires more bits than the CPU has allocated.

Binary to Denary Conversion

To convert from binary to denary, use powers of 2 from right to left and add the values where a 1 appears.

Denary to Binary Conversion

To convert from denary to binary, use place value and subtract the largest possible value.

Hexadecimal Key Concept

Hexadecimal uses sixteen characters: 0-9 stay the same, A=10, B=11, C=12, D=13, E=14, F=15.

Binary to Hexadecimal Conversion

A single Hexadecimal digit represents exactly 4 bits. Split the 8-bit byte in half.

Hexadecimal to Binary Conversion

Convert each individual Hex digit into its own 4-bit binary nibble, then join them together.

Denary to Hexadecimal (via Binary)

Convert Denary to Binary, split that Binary into two nibbles, then convert those nibbles into Hex.

Binary Addition Rules

Binary addition follows four simple rules: 0+0=0, 0+1=1, 1+0=1, 1+1=10 (carry 1).

Pseudocode

A text-based way to write down an algorithm using a structure similar to code, but readable by humans.

Denary/Decimal

The standard human number system using digits 0-9.

Overflow Error Consequences

Can lead to incorrect calculations, data corruption, or program crashes due to exceeding allocated bits.