8.2.2. On Uniform Resource Identifiers
We make use of the definitions given in rfc3986, Uniform Resource Identifier (URI): Generic Syntax. Briefly: a URI consists of a scheme name, separated by a colon from an identifier that is constructed according to the scheme. The http and https schemes are well-known examples. The URIs defined by these schemes may be classified as locators and hence can be called a Uniform Resource Locator (URL).
In the text below, we define three custom schemes for use in Perspectives.