What are the key differences between playing spades and bridge?

The key differences between playing spades and bridge are in the number of players, the deck of cards used, the bidding process, and the scoring system. Spades is typically played with four players using a standard 52-card deck, while bridge is played with four players using a 52-card deck as well. In spades, players bid on the number of tricks they think they can win, while in bridge, players bid on the number of tricks they think they can win and the trump suit. The scoring system in spades is based on the number of tricks won, while in bridge, the scoring is more complex and involves both the number of tricks won and the contract bid.