Lambda for Dummies…anyone, anyone? I think not

Question

In my quest to understand the very odd looking \' => \' operator, I have found a good place to start, and the author is very concise and clear:

Answer 1

Lambda calculus is common in many programming languages. They're also called anonymous functions in some languages. Though different languages have different syntax for lambda, the principle is the same, and their various parts are usually identical.

Perhaps the most famous one is Javascript's anonymous functions.

lol = function() {laugh()}
# is equivalent to
function lol() {laugh()}

What's the difference? Well, sometimes you don't want to go through the trouble of creating a function just to pass it somewhere once and then never again.

window.onload = function() {laugh()}
# is way easier than
function lol() {laugh()}
window.onload = lol

You can see the wikipedia article for indept information or you can skip directly to Lambda in programming in the same article.