A few things to keep in mind about mark prices:
1) Mark prices are primarily calculated using a price index based on prices from multiple spot exchanges, combined with data such as the basis and funding rate.
2) The latest traded price is the price of the most recent trade in the contract market. A large market order can cause a temporary price spike or wick.
3) When setting a stop loss, consider which price should trigger it: triggering on the latest price is more responsive, while triggering on the mark price is less likely to be activated by a false wick.
Today's market: $BTC is at 81750.01, up 1.96% over 24h.