JSFiddle provides an online sandbox for testing snippets of HTML, CSS, and Javascript. Users enter code in each of these languages into the corresponding panel, press 'run', and a fourth panel displays the result. JSFiddle supports streamlined loading of most popular Javascript libraries. Rather than vanilla Javascript, users may also employ Typescript or CoffeeScript. JSFiddle also provides a...

Thonny is an integrated development environment for Python designed specifically for beginning programmers. It presents a simple user interface that was designed to be easy to explore and learn. The built-in debugger features several ways to visualize the execution of code. Particularly useful for beginners is Thonny's "faithful representation of function calls" where each function's context is...