I have various time-consuming plans for the next few weeks and also need to do quite a bit of reading if I’m to put together a decent update for the Teach Yourself Logic guide for 2016. Hence work on revising the category theory notes — already going at, shall we say, a rather gentle pace — will no doubt slow even more. So I thought I would put online the current version of Category Theory: A Gentle Introduction even though it doesn’t reach a natural break point. So far then, the now fourteen chapters (123 pp.), after introducing categories, consider limits and exponentials (constructions within categories) before moving on to start talking about functors (maps between categories). The category theory page here indicates which chapters to then read in the old notes, if you are feeling suitably enthused!