Roger Ehrenberg proposes this clear breakdown of VC funds into two components: stage entry (broken down into seed funds, classic VCs and growth/alernative investors), and persistence (broken down by follow-on likelihood and emphasis).
The article seems targeted at VCs more than founders, but it's useful for both. For example, if trying to raise money from a VC, you'd be wise to understand their strategy in this context, so you know both what to expect in the current round, and what to expect in the future.
