what do the bid/ask prices mean?
For any trade to take place, the price a buyer is will to pay and the price a seller is willing to accept must match. This does not happen.
So the buyer indicate the max price they are willing to pay. This is call bid [as they are trying to bid for an item and may not get it].
Similarly the seller will indicate the lowest price at which they are will to sell, i.e. the minimum price they ask for an item and may not get it].
So the exchanges always list the bid price, and ask price. So an existing [or new] buyer or seller know the positions and they may increase the bid price or lower the ask price depending on how they deem markets to move.
forward contract and a future contract in this case?
Future contract as agreement between buyer and seller to buy an item at a specified price and a specified future date. Depending on the item, the exchange generally governs most of the parameters including the date when these contracts mature.
Forward contracts are similar to future except that most parameters are customised between buyer and seller.