Income statement (P&L) — A statement of revenue, costs and profit over a period. Revenue − COGS = gross profit; gross profit − OpEx = operating profit.
Lessons that explain it
The words everyone assumes you know — Founder vs CEO, shareholder vs employee, customer vs user, revenue vs profit, valuation vs cash, equity vs salary. Twenty minutes here saves a lot of nodding along in meetings. (15 min)
Revenue, costs and profit — The three numbers everything else is built on, and the difference between the money that comes in and the money you keep. (10 min)
MRR and ARR — Recurring revenue is the number investors care about most — and the one founders most often calculate wrongly. (10 min)
Reading an income statement — The P&L, top to bottom. Fifteen minutes and you will never be lost in an accountant's email again. (12 min)