Added more detail on repo structure

Author: TeraMika

README.md

@@ -3,4 +3,18 @@ For the storage of files featured in and pertaining to the virtual Python worksh
 
 The course takes a four-lesson structure, spaced over most of a week. The model code follows this structure.
 
-See 'Notebooks_at_home.docx' for instructions on how to use the notebooks interactively outside of the scheduled webinars, without installing Jupyter Notebooks (if you install JupyterLab/Anaconda you can use those too!).
+### Python Lessons
+
+Contains:
+- Four lesson notebooks
+
+- Summary notebooks `Glossary` (summarising the content of all the lessons as a reference) and `Errors` (brief description of common error types and how to ask for help in the sessions).
+
+- Folder of images for the notebooks.
+
+### Model Code
+
+Contains:
+- A python file for each exercise, following the content of the lessons in order.
+
+- A folder of code for specific exercises, either recurring ones across the lessons (such as guessTheNumber) or full versions of ones such as hangman and noughtsAndCrosses which appear in other exercises.