Who is Truckers from Travels with Charley: In Search of America and what is their importance?

Steinbeck discovers that Truckers have their own unique culture in the United States, He first meets them at a truck stop along a superhighway, where the author queues up for gas with them. Steinbeck mostly listens as the truckers talk among themselves. Their concerns revolve around schedules and routes, not the country. They, like sailors, know little about the world through which they move.