JavaScript
How to use var, let and const in modern JavaScript for ES6+
You should use const and let in most cases in your modern JavaScript code.
ReadHow to build/concatenate a string in JavaScript
You can use Template Literals (Strings) in ES6 to concatenate strings. Also, you can use string interpolation and multi-line strings here.
ReadHow to validate an email in JavaScript
This is not a good idea to use a regular expression to validate an email address in JavaScript. If you are okay with some disadvantages, there is an option.
ReadHow to use for...in and for...of in JavaScript
for...in and for...of in JavaScript help us iterate over properties(keys) and values of an object.
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