How to understand JS expressions and JS statements

JS expression

Expression will Generate a value , It can be placed anywhere you need a value , such as , As an argument to a function call

give an example ：

• a ( A declared variable )
• a+b （ Calculation expression ）
• function(1) （ Function return value ）
• x === y ? ‘a’ : ‘b’ ( Ternary expression )

JS sentence

Can be understood as an act , Do something

• if(){}
• for(){}
• switch(){}