What is URL encoding ? known also as Percent-encoding

About

In a URL / Uniform Resource Identifier (URI), you have reserved character that are part of the URL syntax that cannot be used.

For instance:

• the scheme separator :
• or the path separator /

Percent-encoding, also known as Url Encoding maps (ie encode) :

• this reserved characters
• to text that starts with a percent (hence percent encoding)

Example:

Although it is known as URL encoding it is, in fact, used more generally within the main Uniform Resource Identifier (URI) set, which includes both:

• Uniform Resource Locator (URL)
• and Uniform Resource Name (URN).

Purpose

The purpose detailed is:

• protecting characters from being interpreted as special/reserved URL delimiters,
• protecting URLs from being mangled by transmission media with character conversions (like some email systems).

Snippet

let uri = "sftp://hostname\\foo:Pwd#Pwd@host:port";
console.log("The encoded URI is: "+encodeURI(uri));

Reserved Character

^{1) 2)}