plugins_url()

plugins_url() — Retrieves a URL within the plugins or mu-plugins directory. Defaults to the plugins directory URL if no arguments are supplied.

Inputs: $path (string): Optional. Extra path appended to the end of the URL, including the relative directory if $plugin is supplied. Default empty. $plugin (string): Optional. A full path to a file inside a plugin or mu-plugin. The URL will be relative to its directory. Default empty. Typically this is done by passing _FILE_ as the argument.

Returns string: Plugins URL link with optional paths appended.