Dilution
The reduction in your ownership percentage when new shares are issued (a raise, an option pool).
Why it matters
You can own a smaller slice of a much bigger pie — but know the trade you're making.
Related terms
Valuation (Pre / Post-money)
What your company is worth in a round. Pre-money is before the new investment; post-money adds it in.
SAFE (SAFE)
Simple Agreement for Future Equity — a fast way to raise early money that converts to shares at your next priced round.
Cap Table
The spreadsheet of who owns what — founders, investors, employees (the option pool).
Vesting
Earning your equity over time (commonly 4 years with a 1-year 'cliff') instead of all at once.