What is a lambda (function)?

Question

For a person without a comp-sci background, what is a lambda in the world of Computer Science?

Answer 1

It is a function that has no name. For e.g. in c# you can use

numberCollection.GetMatchingItems(number => number > 5);

to return the numbers that are greater than 5.

number => number > 5

is the lambda part here. It represents a function which takes a parameter (number) and returns a boolean value (number > 5). GetMatchingItems method uses this lambda on all the items in the collection and returns the matching items.