Variable

• variables are lable that references a value.
• variables are used to store information to be reference and manipulated in a computer program.
• variables holds information/data.
• storing information.

let name = 'Manikandan';
    let        -> start with  //(let, var, const)
    name       -> variable identifier
    Manikandan -> information/data
    ;          -> end of the statement

var

• var is function-scope.

• Variables defined with 'var', redeclare and reassign is possible.

let

• let is block-scope

• Some lines of code will written in { } these parentheses, it

• is called block-scope.

• block-scope Variable cannot be access outside the block.

• Variables defined with 'let', must be declare before use/assign value.
• Once declare a Variable with 'let', after re-assign is possible but redeclare is impossible.

const

• const is block-scope.
• variable define with 'const', cannot be redeclare and cannot be reassign.