Dumb question here, I don't really understand what an option is in this context - can you just think of it as a call with a expiration of the vesting date and strike price at whatever they set? So they're giving you calls, with a $0 premium?
It's a call option, with no premium paid, a strike price specified [typically the last 409A valuation or other better proxy of current value], subject to vesting [cannot exercise before this date], but with an expiration some number of years into the future (typically 10 years from the date of the grant).
So you had it basically correct, except they don't expire at the vesting date.
