Content Introduction alert (alert("It's is an alert!!") Hello JavaScript () Comments (for commenting single line select the section the "ctrl+/" or double slash(e.g;-> //Hello world), for commenting on multiple lines (e.g;-> /*Hello world*/)) Variables--- There are 3 keywords when it comes to variables (var Constants Keywords Datatypes Function---Normal Function, Expression Function, Function Parameters & arguments, Return value from function, Arrow function, Methods & functions, Foreach method. Variables There are 3 keywords when it comes to variables (var, let, const) Example-1> var x=10; console.log(x); -------F12---console---- output:10 Example-2> var x=10; console.log(x); var x=15...