Docs: Define TLS/SSL terminology (#30533)

* Docs: Define TLS/SSL terminology

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

* Apply suggestions from code review

Co-authored-by: Ursula Kallio <73951760+osg-grafana@users.noreply.github.com>

* Change title

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

* Move terminology.md

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

Co-authored-by: Ursula Kallio <73951760+osg-grafana@users.noreply.github.com>

contribute/engineering/terminology.md

+# Grafana technical terminology
+
+<!-- Keep terms in alphabetical order: -->
+
+This document defines technical terms used in Grafana.
+
+## TLS/SSL
+
+The acronyms [TLS](https://en.wikipedia.org/wiki/Transport_Layer_Security) (Transport Layer Security and 
+[SSL](https://en.wikipedia.org/wiki/SSL) (Secure Socket Layer) are both used to describe the HTTPS security layer,
+and are in practice synonymous. However, TLS is considered the current name for the technology, and SSL is considered
+[deprecated](https://tools.ietf.org/html/rfc7568). 
+
+As such, while both terms are in use (also in our codebase) and are indeed interchangeable, TLS is the preferred term. 
+That said however, we have at Grafana Labs decided to use both acronyms in combination when referring to this type of 
+technology, i.e. _TLS/SSL_. This is in order to not confuse those who may not be aware of them being synonymous,
+and SSL still being so prevalent in common discourse.