This poster from the Click It or Ticket Mobilization Media Campaign uses twoo techniques.
One is using memorable and emotional language. The poster makes the viewer think about a loved one that may be injured or even killed because of not using a seatbelt. This helps persuade them to tell others to use it when driving.
The other one is formatting pieces of text in different ways. The words are written in different parts of the poster, with different sizes and colours, which helps persuades the viewer in a visual way.
