docs: update core concepts page (#1223)

* fix(docs): core-concepts

* chore(docs): line length

Author: michael-johnston

docs/concepts/core-concepts.md

@@ -3,13 +3,12 @@
 `ado` is a tool for systematically exploring, measuring, and analysing a space
 of entities - for example, configurations, systems and substances. It is built
 on three core concepts: **Discovery Space**, **Operation** and **Sample Store**.
-In brief, you define a Discovery Space, apply an Operation to it, and store the
-results in a Sample Store.
+In brief, you define a Discovery Space, apply an Operation to it, and the
+results are automatically store in a Sample Store.
 
 ## Discovery Space
 
-A **Discovery Space** defines how to answer the following questions: three
-questions:
+A **Discovery Space** answers the following questions:
 
 | Question                            | Concept                                             | Description                                                                                                                                |
 | ----------------------------------- | --------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ |
@@ -31,17 +30,17 @@ Discovery Space.
 Defining an Operation involves specifying the `operator` to use (the Python
 module that implements the operation) and the parameter values to set.
 
-There are two broad classes of Operation: explore operations sample and measure
-points from a Discovery Space; analysis operations process the data currently
-collected in a Discovery Space to provide insights.
+There are two broad classes of Operation: **explore** **operations** sample and
+measure points from a Discovery Space; **analysis** **operations** process the
+data currently collected in a Discovery Space to provide insights.
 
 You can run multiple explore operations on the same space. Each one can select
 and measure new points, increasing the total amount of information available on
 entities in the space. You can always view the entities sampled by each
 Operation independently.
 
-The fact that the Discovery Space exists independently from any particular
-Operation is a central innovation of `ado`.
+The fact that a Discovery Space exists independently of any particular Operation
+on it is a central innovation of `ado`.
 
 ## Sample Store