Modern JavaScript from the Beginning - Second Edition - Block Scope

The video tutorial explains the concept of block level scope and the differences between using var, let, and const to declare variables. It demonstrates how var is not block scoped, unlike let and const, which are. The tutorial includes examples of using let in loops and highlights the function scope of var. It also discusses how global variables declared with var are added to the window object, unlike those declared with let or const.

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