Putting it all together
Every module so far has shown you a snapshot: a payoff at expiry, a Greek at one moment, a strike at entry. The simulator stitches those ideas together — pick a ticker and a strategy, then scrub through a simulated price path day by day and watch the position's value evolve before expiry, not just at the end.
What changes day to day
As the stock price moves and time passes, the position's value reflects both at once: intrinsic value chasing the stock, and theta quietly eating away at it the whole time. Notice how the P&L curve doesn't move in lockstep with the stock price — a flat stock price with time passing still drifts the P&L, because of decay alone.
A sandbox, not a system
This is intentionally a "what-if" sandbox: nothing is saved, there's no account balance, and the price path is simulated rather than real. The point isn't to predict what a real trade would have done — it's to build the instinct for how a position's value actually moves over its life, so the next time you watch a real position before expiry, it won't be a mystery why the P&L moved when the stock barely did.
That's the whole arc of this series: from "what is an option" to watching one breathe day by day. From here, the only way to build real intuition is to start tracking a few trades — paper or small and real — and see how closely reality tracks what you've practiced here.