Applying a conscious set of processes to the acquisition, classification, development, repurposing and sharing of new, personally-applicable knowledge.
>a collection of processes that a person uses to gather, classify, store, search, retrieve and share knowledge in their daily activities -- Grundspenkis, J. (2007), "Agent based approach for organization and personal knowledge modelling: knowledge management perspective", Journal of Intelligent Manufacturing, 18 (4): 451–457 journal -- via wikipedia
PKM as commonly discussed is intrinsically about the use of internet-enabled Tools for Personal Knowledge Management, and the connection of ideas from different sources, so is therefore an instance of Connectivism.
Many practitioners draw from multiple sources and disciplines, so PKM is also often an example of Integrative Learning.
A common challenge for all forms of knowledge management, including PKM, is how to go about Categorising Things
As well as relating theories of learning to PKM, we might also consider Contributions to PKM from NeuroScience.