The melody of Rude Boy by Rihanna runs 678 notes across 47 bars, 3:21 long in Em at 86 beats per minute. The tab sits almost entirely in the first two frets, one note at a time — no chords to barre and no strumming pattern to keep up with. A piano backing track plays the chords and bass underneath, so the line you are learning sounds like the record even at half speed.
Prefer to strum and sing it instead? Rude Boy chords and lyrics.