What is the difference between the middle 8 and the bridge in a song structure?

The middle 8 is a section in a song that typically occurs after the second chorus and provides a contrast to the rest of the song. It is usually eight bars long and often introduces new melodies or lyrics. The bridge, on the other hand, is a section that connects two parts of a song, often providing a sense of transition or buildup to the final chorus. It can feature different chords, melodies, or lyrics compared to the rest of the song.