This is a HL7 FHIR server, and as you appear to be accessing this page from a web browser you are seeing a HTML version of the requested resource(s). You can also access this URL from a FHIR client as a ReSTful API call. For more details please see the HL7 FHIR specification.
<CodeSystem xmlns="http://hl7.org/fhir">
<id value="CareConnect-DeliveryChannel-1"></id>
<text>
<status value="generated"></status>
</text>
<url value="https://fhir.hl7.org.uk/STU3/CodeSystem/CareConnect-DeliveryChannel-1"></url>
<version value="1.0.0"></version>
<name value="CareConnect-DeliveryChannel-1"></name>
<status value="draft"></status>
<date value="2019-12-02T12:10:00+00:00"></date>
<publisher value="HL7 UK"></publisher>
<description value="A CodeSystem that identifies the delivery channel of an appointment."></description>
<copyright value="Copyright © 2019 HL7 UK"></copyright>
<caseSensitive value="true"></caseSensitive>
<content value="complete"></content>
<concept>
<code value="In-person"></code>
<display value="In-person"></display>
</concept>
<concept>
<code value="Telephone"></code>
<display value="Telephone"></display>
</concept>
<concept>
<code value="Video"></code>
<display value="Video"></display>
</concept>
</CodeSystem>