Retrieve a URL and get back an HTTP response:

Use a second argument to get different elements of the HTTP response:

More complex requests can use HTTPRequest:

Build a URL from components:

Changing query parameters and scheme for a given URL:

To specify parameters with the same name, you can use a list of rules:

Or they can be grouped in a list:

Grouping parameters in a list is useful when working with associations, since they do not allow repeated keys:

If no "Method" is specified, "GET" is used automatically:

The body can be a raw string:

Or the body can be a file:

To send an HTTP request where the body is URL encoded, you can just send a list of values. If no "Method" is specified, "POST" is used automatically:

To send files, just use the file object:

To send a more complex file specification, you can use Association:

Content in the Association can be a string, a ByteArray, or a File:

File and CloudObject are fully supported:

Use URLDownload to store output in a file:

Use Get for loading Wolfram Language expressions directly over HTTP:

Import the request by using Import or URLExecute:

Network requests can go wrong for several reasons; messages are sent to help you debug possible causes, and a Failure object is returned:

The Failure object contains the HTTPRequest object:

Import an APIFunction: