The build_query is a WordPress standard function. The build_query function can be used for building URL queries. The & character is used as a parameter separator.
Function Description
This function builds a URL query based on an associative/indexed array.
What does this function returns?
build_query returns a String. URL with request parameters.
Function Parameters
$ data (array) (required)
Key/value pairs from which builds query parameters for the URL.
Source of this function
wp-includes/functions.php
Notes
The opposite operation can be done using the wp_parse_str function.
Function examples
#1 Demonstration of the function
#2 Example of creating a request
