Описание тега minify

A minifier is a tool to perform minification on set of text, most notably source code. In web development, page load times are important, so reducing the file size of JavaScript source files helps reduce the time it takes for the code to be downloaded over an Internet connection.

Minification is the practice of removing unnecessary characters from code to reduce its size. For developmental purposes, programmers use whitespace characters (spaces, tabs, carriage returns, etc.) to format source code in a way that is easier for humans to read.

The computers and software that consumes this code does not care at all about how it is formatted, so removing these characters will not alter the code's functionality at all.

Un-minified Example:

var myArray = [];
for (var i = 0; i < 20; i++) {
  myArray[i] = i;
}

Minified Example:

for(var a=[i=0];++i<20;a[i]=i);

Both of the examples perform the same task of iterating through 20 numbers and adding them to an array.

In addition to whitespace removal, minifiers will also rename variables to shorter names and possibly refactor some logic in ways that yield the same outcome.