Modifications to introductory paragraph

Signed-off-by: Daniel Neilson <[email protected]>

wiki/Introduction-to-Creating-a-Job.md

@@ -1,9 +1,12 @@
 # Introduction to Creating a Job
 
-This page guides you through developing a Job using Open Job Description. Going through this guide will introduce you to the 
-[Open Job Description CLI](https://pypi.org/project/openjd-cli/) to develop and test jobs without needing to submit them
-to a compute cluster, and how to configure the [Visual Studio Code](https://code.visualstudio.com/) editor to help you write
-Open Job Description templates.
+This page guides you through developing a Job using Open Job Description. A Job in Open Job Description
+is a set of commands that are run on distributed compute hosts subject to ordering, parallelism,
+and other hardware and scheduling constraints. Open Job Description defines Jobs via a Job Template that
+describes the Job's shape, runtime environment, and the processes that will run. So, creating a Job is an exercise in creating
+a Job Template. Going through this guide will introduce you to the [Open Job Description CLI](https://pypi.org/project/openjd-cli/)
+to develop and test jobs without needing to submit them to a compute cluster, and how to configure the
+[Visual Studio Code](https://code.visualstudio.com/) editor to help you write Open Job Description templates.
 You will also go through a gradual introduction to constructing Job Templates to define your Jobs that shows
 you how to: