Python Lessons

A collection of free, in-depth Python lessons for beginners on core topics.

Lambda Functions in Python

Lambda functions in Python is a feature that allows you to create small, inline functions without the need for a definition using the def keyword. Lambda functions, are particularly useful when you need to create simple functions on the fly, for one-time use for tasks such as filtering, mapping, and sorting data. Because lambda functions are not defined with a name, they are also known as anonymous functions.

Python Optional Parameters

Sometimes, you may encounter situations where you want a function to work a certain way most of the time, but also have the option of changing its behavior occasionally. This is where Python optional parameters come in. Optional parameters allow you to define functions with parameters that have default values. These default values are used when an argument is not provided during the function call.

Python Keyword Arguments in Function Calls

In Python, keyword arguments allow you to pass arguments to a function by specifying the names of the parameters. This approach matches the values passed to the function and its parameters according to the parameter names rather than the order in which they appear. This makes function calls more explicit and self-documenting, as you provide the values along with their corresponding parameter names.

Python Functions

Functions are an essential aspect of programming that allow you to encapsulate a set of instructions and logic into a reusable block of code. They enhance code organization, readability, and maintainability. A Python function is a named sequence of statements that performs a specific task. It takes input data, processes it, and optionally returns a result.

Python List

A Python list is a collection of ordered items. Lists can hold a mix of items of any data type and can also change their size. Consequently, Python lists are very easy to use. However, their flexible nature comes at the expense of performance (speed and space usage) as well as an increased potential for bugs.