Added definitions page

Author: PhilReedData

TeSS_docs/_toc.yml

@@ -7,6 +7,7 @@ parts:
   - caption: Overview
     chapters:
     - file: overview/tess
+    - file: overview/definitions
   - caption: Account creation
     chapters:
     - file: accounts/user

TeSS_docs/overview/definitions.md

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+# Definitions
+
+Definitions of terms and user roles.
+
+## Terms 
+
+Definition of common terms used across TeSS.
+
+### Exchange (TeSS-X)
+
+If a community runs its own instance then a TeSS-X plugin sets up an exchange with other instances.
+In the mTeSS-X project, we will show how several TeSS-instance catalogues exchange nominated training resources. 
+See [What do we mean by eXchange?](https://elixirtess.github.io/mTeSS-X/exchange) on the mTeSS-X project website for details.
+
+
+### Instance
+
+One installation of the TeSS Platform, on a server, managed by a technical administrator. An instance may have multiple spaces, if this option has been enabled by the administrator.
+
+Examples of TeSS instances can be viewed on the [global usage page](https://elixirtess.github.io/mTeSS-X/global) of the mTeSS-X project website.
+
+
+### mTeSS-X Project
+
+The [mTeSS-X Project](https://elixirtess.github.io/mTeSS-X) (Multi-space Training e-Support System with eXchange) overcomes the fragmentation of training resources across Research Infrastructures and the European Science Clusters.
+The project aims to enhance existing TeSS-based training registries or catalogues like [ELIXIR TeSS (life sciences)](https://tess.elixir-europe.org/) and [PaN-Training (photon and neutron)](https://www.panosc.eu/training-catalogue/) by building an aggregator for these and similar platforms.
+
+
+### Space (mTeSS)
+
+A single TeSS instance presents multiple tailored spaces (catalogues) whose selections of training material are “views” on a global catalogue. 
+Each community registers, maintains and curates their material for their members in their own virtual space in the common portal environment.
+See [What do we mean by Multi-space/tenancy?](https://elixirtess.github.io/mTeSS-X/multi-space) on the mTeSS-X project website for details.
+
+
+### TeSSHub
+
+The first TeSS instance with multiple spaces. This will be one of the outputs from the mTeSS-X project, where [ELIXIR TeSS (life sciences)](https://tess.elixir-europe.org/) and [PaN-Training (photon and neutron)](https://www.panosc.eu/training-catalogue/) will be multipe spaces running from the same server, appearing as distinct catalogue. 
+
+Communities will be welcome to request their own space on the TeSSHub, providing them with their own registry, without the need to host and maintain their own instance.  
+
+
+### TeSS Platform
+
+The main codebase which is used for development, written in Ruby on Rails. The code is open source and [available on GitHub](https://github.com/ElixirTeSS/TeSS) under a BSD 3-Clause licence. 
+
+
+### TeSS Portal
+
+Shorthand for the [ELIXIR TeSS](https://tess.elixir-europe.org/) portal, the training registry for Europe's distributed infrastructure for life-science data, built using the TeSS Platform. 
+
+
+
+## Roles
+
+Definitions of user roles in TeSS. 
+
+### Administrator
+
+The technical administrator, responsible for installation, configuration and maintenance of a TeSS instance.
+
+### Curator
+
+A person with limited administrator permissions.
+
+### Space Manager
+
+The person responsible for managing a space within an instance.

TeSS_docs/overview/tess.md

@@ -1,3 +1,19 @@
 # Introduction to TeSS
 
-[ELIXIR TeSS](https://tess.elixir-europe.org/)
+**Training e-Support Service (TeSS)**
+
+TeSS is a platform that was developed to provide a one-stop shop for trainers and trainees to discover online information and content, including training materials, events and interactive tutorials. 
+For training providers, TeSS provides opportunities to promote training events and news, and to contribute to a growing catalogue of materials; 
+for trainers, the portal offers an environment for sharing materials and event information; 
+for trainees, it offers a convenient gateway via which to identify relevant training events and resources, and to perform specific, guided analysis tasks via customised training workflows.
+
+The [mTeSS-X Project](https://elixirtess.github.io/mTeSS-X) (Multi-space Training e-Support System with eXchange) overcomes the fragmentation of training resources across Research Infrastructures and the European Science Clusters. 
+The project aims to enhance existing TeSS-based training registries or catalogues like [ELIXIR TeSS (life sciences)](https://tess.elixir-europe.org/) and [PaN-Training (photon and neutron)](https://www.panosc.eu/training-catalogue/) by building an aggregator for these and similar platforms.
+
+TeSS was originally developed as part of [ELIXIR](https://elixir-europe.org/), Europe's distributed infrastructure for life-science data. 
+One of the goals of ELIXIR is to train research scientists to better use available computational infrastructures to address critical research questions. 
+This requires access both to face-to-face training opportunities and to disparate training materials and resources, currently dispersed across Europe.
+
+
+
+