Exploratory Testing Foundations is a basic course to exploratory testing (incl. test automation). One fairly simple application, unintentional bugs to discover, and details of applying different constraints to how you look at the application to see them. 

Published with Creative Common Attribution. Yes, no NC, no SA. Take whatever you find useful and make the world of testing a little better. 

https://dev.to/maaretp/exploratory-testing-foundations-4lb3