switch badge and minor changes to key concepts

README.md

@@ -2,7 +2,7 @@
 
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@@ -24,39 +24,44 @@ A lightweight, object-oriented state machine implementation in Python with many
 
 ## Table of Contents
 
-- [Quickstart](#quickstart)
-- [Non-Quickstart](#the-non-quickstart)
-  - [Some key concepts](#key-concepts)
-  - [Basic initialization](#basic-initialization)
-  - [States](#states)
-    - [Callbacks](#state-callbacks)
-    - [Checking state](#checking-state)
-    - [Enumerations](#enum-state)
-  - [Transitions](#transitions)
-    - [Triggering a transition](#triggers)
-    - [Automatic transitions](#automatic-transitions-for-all-states)
-    - [Transitioning from multiple states](#transitioning-from-multiple-states)
-    - [Reflexive transitions from multiple states](#reflexive-from-multiple-states)
-    - [Internal transitions](#internal-transitions)
-    - [Ordered transitions](#ordered-transitions)
-    - [Queued transitions](#queued-transitions)
-    - [Conditional transitions](#conditional-transitions)
-    - [Check transitions](#check-transitions)
-    - [Callbacks](#transition-callbacks)
-  - [Callable resolution](#resolution)
-  - [Callback execution order](#execution-order)
-  - [Passing data](#passing-data)
-  - [Alternative initialization patterns](#alternative-initialization-patterns)
-  - [Logging](#logging)
-  - [(Re-)Storing machine instances](#restoring)
-  - [Extensions](#extensions)
-    - [Diagrams](#diagrams)
-    - [Hierarchical State Machine](#hsm)
-    - [Threading](#threading)
-    - [Async](#async)
-    - [State features](#state-features)
-    - [Django](#django-support)
-  - [Bug reports etc.](#bug-reports)
+- [ transitions](#-transitions)
+  - [Installation](#installation)
+  - [Table of Contents](#table-of-contents)
+  - [Quickstart](#quickstart)
+  - [The non-quickstart](#the-non-quickstart)
+    - [Some key concepts](#some-key-concepts)
+    - [Basic initialization](#basic-initialization)
+    - [States](#states)
+      - [Callbacks](#callbacks)
+      - [Checking state](#checking-state)
+      - [Enumerations](#enumerations)
+    - [Transitions](#transitions)
+      - [Triggering a transition](#triggering-a-transition)
+      - [Triggering invalid transitions](#triggering-invalid-transitions)
+      - [Automatic transitions for all states](#automatic-transitions-for-all-states)
+      - [Transitioning from multiple states](#transitioning-from-multiple-states)
+      - [Reflexive transitions from multiple states](#reflexive-transitions-from-multiple-states)
+      - [Internal transitions](#internal-transitions)
+      - [ Ordered transitions](#-ordered-transitions)
+      - [Queued transitions](#queued-transitions)
+      - [Conditional transitions](#conditional-transitions)
+      - [Check transitions](#check-transitions)
+      - [Callbacks](#callbacks-1)
+    - [Callable resolution](#callable-resolution)
+    - [Callback execution order](#callback-execution-order)
+    - [Passing data](#passing-data)
+    - [Alternative initialization patterns](#alternative-initialization-patterns)
+    - [Logging](#logging)
+    - [(Re-)Storing machine instances](#re-storing-machine-instances)
+    - [ Extensions](#-extensions)
+      - [ Diagrams](#-diagrams)
+    - [Hierarchical State Machine (HSM)](#hierarchical-state-machine-hsm)
+      - [Reuse of previously created HSMs](#reuse-of-previously-created-hsms)
+      - [ Threadsafe(-ish) State Machine](#-threadsafe-ish-state-machine)
+      - [ Using async callbacks](#-using-async-callbacks)
+      - [Adding features to states](#adding-features-to-states)
+      - [ Using transitions together with Django](#-using-transitions-together-with-django)
+    - [I have a \[bug report/issue/question\]...](#i-have-a-bug-reportissuequestion)
 
 ## Quickstart
 
@@ -186,15 +191,15 @@ 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.