How-To Guides
Task-focused guides that show you the right way to get one specific thing done — with runnable code.
How to Merge Objects in JavaScript
Merge two or more objects with the spread operator or Object.assign(), understand how key conflicts resolve, and know why both do a shallow merge.
JavaScriptHow to Remove Duplicates from an Array in JavaScript
Get the unique values from an array — with a one-line Set for primitives, and a Map when you need to de-duplicate objects by a key.
JavaScriptHow to Reverse a String in JavaScript
Reverse a string with the split–reverse–join one-liner, understand why each step is needed, and handle emoji and accented characters correctly.
JavaScriptHow to Sort an Array in JavaScript
Sort numbers, strings, and objects correctly with Array.prototype.sort() — and avoid the default-sort trap that turns [10, 1, 2] into [1, 10, 2].
How to Loop With an Index in Python
Loop over a list and get each item's position at the same time using enumerate() — the clean, Pythonic alternative to range(len(...)), including how to start the count at one.
PythonHow to Merge Dictionaries in Python
Merge two or more dictionaries with the | operator, dictionary unpacking, or update() — understand how key conflicts resolve and which approach mutates.
PythonHow to Reverse a String in Python
Reverse a Python string the idiomatic way with the slice s[::-1], or with reversed() and join() when you want the intent spelled out — and learn why there is no str.reverse() method.
PythonHow to Sort a List in Python
Sort a Python list two ways — in place with list.sort(), or into a new list with sorted() — and order by length, case, or a dictionary key with the key= argument.
A how-to answers one practical question — "how do I sort an array?", "how do I remove duplicates?" — with the clearest correct solution, not a wall of theory. Each guide gives you the recommended approach, the reason it's recommended, the common pitfalls, and code you can run and adapt immediately.
Where several approaches exist, the guide shows the modern, idiomatic one first, then explains the trade-offs of the alternatives so you can choose deliberately. Every snippet is tested before it ships, and most run live on the page.
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Frequently asked questions
What's the difference between a how-to and a reference page?
Array.sort) in full. A how-to solves a real task (like "sort an array of objects by a field"), which may combine several features, and focuses on the recommended solution and its pitfalls.