switch badge and minor changes to key concepts

README.md

@@ -2,7 +2,7 @@
 
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@@ -26,7 +26,7 @@ A lightweight, object-oriented state machine implementation in Python with many
 
 - [Quickstart](#quickstart)
 - [Non-Quickstart](#the-non-quickstart)
-  - [Some key concepts](#key-concepts)
+  - [Some key concepts](#some-key-concepts)
   - [Basic initialization](#basic-initialization)
   - [States](#states)
     - [Callbacks](#state-callbacks)
@@ -186,15 +186,15 @@ Have a look at the [Diagrams](#diagrams) extensions if you want to know how.
 
 ## The non-quickstart
 
-A state machine is a _model_ of behavior composed of a finite number of _states_ and _transitions_ between those states. Within each state and transition some _action_ can be performed. A state machine needs to start at some _initial state_.
+A state machine is a _model_ of behavior composed of a finite number of _states_ and _transitions_ between those states. Within each state and transition some _action_ can be performed. A state machine needs to start at some _initial state_. When using `transitions`, a state machine may consist of multiple objects where some (_machines_) contain definitions for the manipulation of other (_models_). Below, we will look at some core concepts and how to work with them.
 
 ### Some key concepts
 
 - **State**. A state represents a particular condition or stage in the state machine. It's a distinct mode of behavior or phase in a process.
 
 - **Transition**. This is the process or event that causes the state machine to change from one state to another.
 
-- **Model**. Blueprint or structure that holds the state machine. It's the entity that gets updated as new states and transitions are added.
+- **Model**. The actual stateful structure. It's the entity that gets updated during transitions. It may also define _actions_ that will be executed during transitions. For instance, right before a transition or when a state is entered or exited.
 
 - **Machine**. This is the entity that manages and controls the model, states, transitions, and actions. It's the conductor that orchestrates the entire process of the state machine.