Having an accounting 101 level of background (I'm sure there are a lot of good online resources to pick up accounting - the basics of accounting are way easier than the basics of computer science IMO)gets you like 90% of the way there to be able to skip down to the financial statements and the footnotes and get a decent sense of what the company looks like. Obviously you can go further and further in depth, and there are a lot of things specific to the IPO process that are good to know, but IMO knowing how to look through the accounting statements and read a balance sheet/income statement/statement of cashflows is the 20% of effort needed to get 80% of the insight you would want.