There are three (3) types of URL formats to choose from:

A Standard URL is a typical query string with ? and & to attach value pair parameters.  This format is not search engine optimized (SEO).  Example:  domain.com?name=John&phone=123456789.

An SEO URL is more search engine optimized or friendly then a Standard query string URL becuase it does not use ? or & within the query string.  example: domain.com/name/John/phone/123456789.

A Custom URL is a URL that you specify.  Only use this option if you know what you are doing.