This is a typical example for ... create a function: def dbl(n): return 2*n print(dbl(7)) Of course: I can write simply 2*7, but the idea is to save a complex formula in an object once, and reuse it several times. In this case the Lambda expression saved me one line, and one of the characteristics of Python ... More on discuss.python.org

It's a function that has no name, can only contain one expression, and automatically returns the result of that expression. Here's a function named "double": def double(n): return 2 * n print(double(2)) results in: 4 You can do the same thing without first defining a named function by using a lambda instead - it's creating a function right as you use it: print((lambda n: 2 * n)(2)) You can pass functions into other functions. The map function applies some function to each value of a sequence: list(map(double, [1, 2, 3])) results in: [2, 4, 6] You can do exactly the same thing without having defined double() separately: list(map(lambda n: 2 * n, [1, 2, 3])) More on reddit.com

they're just...functions with different syntax That's exactly what they are. The main syntactical difference between the two is that a regular function definition is a statement, whereas a lambda function definition is an expression. Lambda functions can therefore be defined and then passed to another function in one step, without having to go through a local name (that's also why lambda functions are sometimes called anonymous functions, they don't necessarily have a particular name). Lambda is a convenience feature to more easily define small, one-off functions. More on reddit.com