Expression

An expression is a piece of source code that produces a value at runtime.

Related concepts:  EvaluationValue

Closest Wikipedia entry:  Expression (computer science) — In computer science, an expression is a syntactic entity in a programming language that may be evaluated to determine its value. It is a combination of one or more constants, variables, functions, and operators that the programming language interprets (according to its particular rules of precedence and of association) and computes to produce ("to return", in a stateful environment) another value. This process, for mathematical expressions, is called evaluation.

Misconceptions about Expression

45 documented Misconceptions

ArrowFunctionNoImpliedReturn

Even when an arrow function consists just of an expression, the return keyword must be explicitly written

ArrowFunctionRequiresFunctionKeyword

Arrow functions also require the keyword 'function'

ConditionalOperatorNotExpression

The conditional operator is not an expression

IdentifierAsStringInBracketNotation

An identifier used to access a property with the bracket notation is treated as a string

MandatoryAssignment

An expression must be assigned to have a valid statement

NoAtomicExpression

Expressions must consist of more than one piece

NoFunctionCallsChaining

It is not allowed to chain function calls