JavaScript is a very dynamic language, so much so that you can redefine and change objects on the fly. This can be a strange concept to programmers from a more traditional OO background such as Java or C#, however once made familiar it can be very useful.
This feature is not restricted to modifying your own [...]

What are Lambda functions? Basically lambdas are functions that can be treated as anonymous or as objects. It depends on the language that is being used. They are very useful and at the core of the Functional Programming paradigm. So what languages can you create lambas in? Here is a few;
JavaScript

var foo = function(x, y){

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