Key startup terminology every founder needs to know

Executive overview

New founders constantly encounter jargon that sounds familiar but is poorly understood. Misreading terms like burn rate, product market fit, or TAM can lead to bad fundraising decisions and operational blind spots.

Dalton Caldwell (YC Managing Partner) defines 13 core startup terms with precision — cutting through vague common usage to give founders working definitions they can act on.

The risk isn't not knowing these terms — it's thinking you know them when you don't.

MVP, product market fit, and bootstrapping

• MVP (minimum viable product) must be viable — useful enough to serve a real customer need. A broken or purposeless product does not qualify.
• Product market fit (PMF) is the state where customer acquisition is no longer your biggest problem; growth, scaling, and performance are.
• Pre-PMF: all focus goes to testing assumptions and talking to customers.
• Post-PMF: focus shifts to staying in that state and scaling.
• Bootstrapping means building without venture capital — using personal funds or revenue. Best suited to businesses targeting $5–10M in revenue, not venture-scale growth.

Venture capital, angels, and funding rounds

• Venture capital invests small amounts for equity across many startups, expecting a few outsized winners to return the whole fund.
• Most VC portfolio companies fail; returns depend on rare breakout investments (e.g. early Google, Apple, Facebook).
• Angel investors deploy personal money (not fund capital), write small checks ($20K–$50K), invest at the earliest stage, and treat it as a side activity.
• A seed round is loosely defined as the first meaningful fundraise — size varies enormously, from $300K to $100M in extreme cases.
• Series A/B/C rounds typically involve a lead investor, a board seat, and a significant ownership stake (traditionally ~20% for a Series A lead).
• Later rounds simply increment the letter; round letter alone says nothing about valuation.

Financial instruments: SAFEs and convertible notes

• A convertible note is a debt instrument — it may carry interest and repayment obligations. Read the fine print.
• A SAFE (Simple Agreement for Future Equity), created by YC's Carolyn Levy, is a simpler alternative with fewer terms and fewer investor rights.
• SAFEs are well-suited for closing seed capital quickly ahead of a priced Series A.
• Always read the fine print on any instrument — whether as founder, employee, or investor.

Equity and stock options

• Equity is ownership, expressed as a percentage of the company.
• Employees often receive stock options — the right to purchase equity at a future date — not equity directly.
• Understand exactly what you hold: equity, options, SAFE, or convertible note. They have different rights and timelines.

Revenue metrics: ARR and MRR

• ARR (annual recurring revenue) measures revenue from contracts or subscriptions that renew yearly.
• MRR (monthly recurring revenue) is the equivalent for monthly billing cycles (e.g. SaaS subscriptions).
• The key word in both is recurring — only count revenue that actually renews automatically or contractually.
• Misrepresenting ARR to investors by including non-recurring revenue is a credibility risk.

Burn rate and profitability

• Burn rate is how much your bank balance drops each month. $1M → $900K = $100K burn.
• Founders must monitor burn rate actively; high top-line revenue does not protect against running out of cash.
• Profitability is not just revenue exceeding costs — the important question is whether margins improve at scale.
• Google generated no revenue for years, but its advertising margins were high enough that switching on monetisation produced enormous profit.

TAM and valuation

• TAM (total addressable market) is a thought experiment: how much revenue if 100% of potential customers bought your product?
• TAM calculations are often wrong — great products expand their own market (Uber grew the ridesharing market; Tesla grew the EV market).
• Treat TAM as directional context, not a fixed ceiling.
• Valuation reflects the price at which the last investor bought in — not a liquid market price.
• Startups are privately held; there is no public market to validate that number daily.
• High valuations do not guarantee success.

IPO

• An IPO (initial public offering) is when a private company sells shares on public exchanges (NASDAQ, NYSE).
• It enables founders, employees, and investors to realise returns from the company.
• Generally signals financial maturity and sustained growth, though not a guarantee of long-term success.