A beginners guide to Typescript | Collective Literal Types, Widening and Narrowing Types 

Thank you very much!

Hope this makes it clear typeof expression is the operator that lets you determine the type of expression. typeof evaluates to one of the values: 'string', 'number', 'boolean', 'symbol', 'undefined', 'object', 'function'. typeof null evaluates to 'object', thus the correct way to use typeof to detect an object is typeof object === 'object' && object !== null. instanceof operator let's identify the instance's constructor. object instanceof Constructor evaluates to true if object is an instance of Constructor.

Usually use typeof for primitives, cause when you pass it an object, array, null or ehatever it will just give you back “object” Whereas with instanceof you can check if you pass an array for ex unction isArray(value) { return value instanceof Array; } isArray([1, 2, 3]); // => true isArray({ prop: 'Val' }); // => false

Update out in about 2 weeks!

you are first and managed to edit your comment, gg