What is the % Code in My URL?

In order to prevent the misinterpretation of special characters such as a space, bracket (<>), or % in the URL (which stands for Uniform Resource Locator - it is the address you see in your browser's address bar indicating the location of the website you are visiting), browsers parse certain special characters using escape characters. This explains why when you click on a link such as: domain.com/page one.htm you see it parsed in the address bar as domain.com/page%20one.htm. In this case the %20 is the escape character for the space.
Common URL Escape Characters
Table of URL Escape Characters
Character Escape Character Character Escape Character
Space %20 # %23
$ %24 % %25
& %26 @ %40
' %60 / %2F
: %3A ; %3B
< %3C = %3D
> %3E ? %3F
[ %5B \ %5C
] %5D ^ %5E
{ %7B %7C
} %7D ~ %7E