Day Tripper is a chart topper by Beatles which was released as a double A-side single in 1965. This song has really unique opening guitar riffs that revolve around an E7 chord that gives it a great bluesy feel. The rest of the tune is very simple and basically involves just a few power chords played rhythmically. This is key in most of Beatles songs, which were more about songwriting and playing in the pocket with a solid groove. There's not too much technique to get wrapped up in so this gives you a really good chance to focus on the musicality of your playing.