Query String

Extra Info that can be sent to requested path.
For instance /blog?id=1 would tell the blog path,
"User wants to receive the id of 1 in the blog article"

It uses a name/value pairs
You have a the following below in Query String:

1. question mark (?) separating the rest of the URL from the URL parameters,
2. an equals sign (=) separating each name from its associated value,
3. an ampersand (&) separating each pair.

http://example.com?name=Fred&age=11.