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Code Articles
30 seconds of code contains a curated collection of code articles covering a wide range of development needs. The collection spans many topics, ranging from simple coding problems to theoretical concepts and development techniques.
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JavaScript · How do I remove a property from a JavaScript object?
Ever wanted to delete a property from a JavaScript object? Here are a few way you can accomplish that.
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JavaScript · JavaScript modules Cheat Sheet
Learn everything you need to know about JavaScript modules with this handy cheatsheet.
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HTML · Lazy load images in HTML
Discover how to improve your website's performance by implementing lazy loading for images using a native HTML attribute.
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JavaScript · The order of then and catch matters
Messing up the order of chained
thenandcatchmethods in JavaScript promises can cause problems. Here's a short primer on the subject. -
CSS · CSS easing variables
Learn how to use the
cubic-bezier()class of easing functions and create beautiful animations that stand out. -
JavaScript · Understanding JavaScript variables and scopes
JavaScript developers often get confused by JavaScript's variables and scope. Here's a quick guide to understanding these concepts.
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JavaScript · How to swap two variables in JavaScript
Learn how to swap the values of two variables in JavaScript using a single line of ES6 code.
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CSS · The perfect duration for CSS transitions
Learn how to make your CSS transitions feel perfect when users interact with elements on the page with this simple tip.
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HTML · Protect your users from malicious websites when using target="_blank"
Opening a link in a new tab comes with a security vulnerability that you may not be aware of. Protect your users with this simple trick.
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JavaScript · What's the difference between undeclared, undefined and null in JavaScript?
JavaScript has three different empty states for variables. Learn their differences and how you can check for each one.
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JavaScript · What is the difference between JavaScript's equality operators?
Learn all you need to know about the differences between JavaScript's double equals and triple equals operators.
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HTML · Customize the names of downloadable files
Learn what HTML5 attribute you can use to customize the names of your downloadable files with this quick tip.
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React · React PropTypes - objectOf vs shape
Learn the differences between
PropTypes.objectOf()andPropTypes.shape()and where to use each one with this quick guide. -
Git · Create a commit with a different date
Ever needed to create a git commit with a different date? Here's a quick and easy way to do it.
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Web development · Common HTTP status codes Cheat Sheet
Familiarize yourself with the most common HTTP status codes with this handy cheatsheet.
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Git · How to add multiple authors to a commit
Learn how to add multiple authors to a git commit with this quick and easy tip.
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CSS · CSS units Cheat Sheet
Learn everything you need to know about CSS units with this handy cheatsheet.
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JavaScript · What's the difference between Object.is() and the triple equals operator in JavaScript?
Object.is()and the triple equals operator (===) can both be used for equality checking in JavaScript, but when should you use each one? -
HTML · Add autocomplete to an HTML password field
Use the HTML
autocompleteattribute to create more secure and accessible password fields. -
JavaScript · Debugging Node.js using Chrome Developer Tools
Did you know you can use Chrome Developer Tools to debug your Node.js code? Find out how in this short guide.
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Web development · Bash Shortcuts Cheat Sheet
Maximize your productivity when working with a bash or other shell terminal by using these keyboard shortcuts.