Operators and Expressions
Operators perform calculations and comparisons on values, such as plus, minus, equals and greater than.
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Operators perform calculations and comparisons on values, such as plus, minus, equals and greater than.
- Arithmetic operators calculate
- Comparison operators compare
- Logical operators combine conditions
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Operators and Expressions?
Within Computer Science, which covers algorithms, programming, data, networks, hardware and safe, responsible use of technology, this topic explains Operators and Expressions. Computing topics explain how software, hardware and data work, with diagrams and models that show each step in order.
Check that you can explain Operators and Expressions in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Operators and Expressions helps you design, test and explain programs, websites and systems, from small projects to exam questions.
Operators and Expressions in detail
Operators carry out operations on values. Arithmetic operators include +, −, *, /, and others such as MOD (the remainder) and DIV (the whole-number quotient). Comparison operators (==, !=, <, >, <=, >=) compare values and give True or False, and logical operators (AND, OR, NOT) combine conditions.
An expression combines values, variables and operators to produce a result, such as (price * quantity) - discount. Precedence rules decide the order, with brackets used to control it, similar to BIDMAS. Care is needed with integer division and with the difference between = (assignment) and == (comparison).
How the interactive helps you understand Operators and Expressions
Click a card to flip it and reveal the answer, then move on to the next one.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Operators and Expressions.
Real-life uses and examples
- Recognise Operators and Expressions in an app or device you use every day.
- Apply Operators and Expressions when you design a small program, website or spreadsheet.
- Explain Operators and Expressions to someone new to computing by comparing it to a familiar process.
Common mistakes to avoid
- Using the term without being able to say what the computer actually does.
- Testing only the normal case and forgetting the edge cases.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Operators and Expressions
What is Operators and Expressions?
Operators perform calculations and comparisons on values, such as plus, minus, equals and greater than.
What are the most important points about Operators and Expressions?
The main points are: Arithmetic operators calculate; Comparison operators compare; Logical operators combine conditions.
Why is Operators and Expressions useful?
Understanding Operators and Expressions helps you design, test and explain programs, websites and systems, from small projects to exam questions.
How can I practise Operators and Expressions?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Operators and Expressions?
Related topics in Computer Science include Arrays and Lists, Scope of Variables, Testing and Debugging.