Chasing Cars" by Snow Patrol is an emotional and uplifting ballad about the pursuit of love and the longing for a deeper connection. The song speaks of the desire to find someone to share life\'s journey with, and the hope that the chase will be worth it in the end
From Wikipedia
"Chasing Cars" is a song by Northern Irish alternative rock band Snow Patrol, released on 6 June 2006 in the United States and 24 July in the United Kingdom as the second single of their fourth album, Eyes Open (2006). The song gained significant popularity in the US after being featured in the second season finale of the medical drama Grey's Anatomy, which aired on 15 May 2006.