./ vs directory name in paths and file linking

Question

What is the difference between using ./ and directly writing a directory or file name when working with paths.

Suppose I have the following simple structure:

project
│   index.html  
│
└───pages
│   │   file1.html
│   │   file2.html
│   │
│   └───about
│       │   file3.html
│       │   file4.html

If I am say in file1.html what is the difference between writing the link is the following ways?

<a href="./about/file3.html">Link</a>

vs.

<a href="about/file3.html">Link</a>

Important

I know what ./ means! I just want to know if there is a practical difference & advantage/disadvantage

Answer 1

On the web, as far as I know, the two are functionally equivalent.

However, inside a Node.js application, the ./ differentiates local files from library files (ie. files coming from NPM/node_modules).

In other words:

import Foo from 'foo';

imports the Foo variable from the library called "foo", in node_modules, while:

import Foo from './foo'

would instead import Foo from a file called foo.js in the same directory.