Just campaign hook need to be small to get the idea across as quickly as possible. Grabbing the attention of your potential customers before their short attention span is focused on something else.
Ipod: 1000 songs in your pocket.
Reference
Ferriss, Timothy. The 4-Hour Workweek: Escape 9-5, Live Anywhere, and Join the New Rich. Expanded and Updated ed., 1st revised ed, Crown Publishers, 2009.
Highlights or timestamps
First, you should be able to summarize the product’s purpose in one sentence. When Apple released the iPod way back in 2001, everyone instantly knew what it was for thanks to the accompanying slogan: “1,000 songs in your pocket.”
— ^b56f4f from The 4-Hour Workweek