Tomer Aberbach

/en-US/docs/Glossary/Global_object

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/en-US/docs/Web/JavaScript/Equality_comparisons_and_sameness#Loose_equality_using

/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwn

/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty

/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/prototype

/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object#null-prototype_objects

/en-US/docs/Web/JavaScript/Reference/Global_Objects/ReferenceError

/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined

/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined#:~:text=Note%3A%20While%20you%20can%20use%20undefined%20as%20an%20identifier%20(variable%20name)%20in%20any%20scope%20other%20than%20the%20global%20scope%20(because%20undefined%20is%20not%20a%20reserved%20word)%2C%20doing%20so%20is%20a%20very%20bad%20idea%20that%20will%20make%20your%20code%20difficult%20to%20maintain%20and%20debug.

/en-US/docs/Web/JavaScript/Reference/Operators/in

/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR

/en-US/docs/Web/JavaScript/Reference/Operators/null

/en-US/docs/Web/JavaScript/Reference/Operators/typeof

/en-US/docs/Web/JavaScript/Reference/Operators/typeof#interaction_with_undeclared_and_uninitialized_variables

/en-US/docs/Web/JavaScript/Reference/Operators/void

/en-US/docs/Web/JavaScript/Reference/Operators/void#examples