Even if we’ve arrived at mycology “accidentally”, we find ourselves diving into a daunting pool of knowledge, widened and deepened by centuries of research and discovery. Memorizing a few scientific names and diagnostic characteristics is soon not enough for those of us now held in thrall by fungi; we want more, we need more. We can’t help getting the feeling that “barcoding” and the “ITS region” might be arcane topics, but understanding modern methodologies of fungal identification and phylogeny has already become essential. But how and where to start? The comprehensive overview provided in a college-level Mycology course would be the obvious way, but that may not be a feasible option for most of us. This lecture is intended to provide an overview of the kingdom fungi (including phyla such as slime molds and water molds, once considered fungi) and the history of nomenclature and taxonomy (including traditional morphology-based, and current molecular-based methods). Hopefully the lecture will provide an organizational framework for the avalanche of new information coming our way as “accidental mycologists”. The crucial importance of fungi in the biosphere is finally being revealed, and the field of mycology is starting to get the recognition it deserves.