What do blue signs with white lettering typically indicate?

Blue signs with white lettering are guide signs that indicate motorist services and information — such as gas stations, food, lodging, rest areas, and hospitals — often near highway exits. The blue color is reserved for these service-related guide signs, helping travelers find what they need. Brown signs, by contrast, mark recreational and cultural points of interest (parks, historic sites), and green signs give directional and distance information. Distinguishing the guide-sign colors (green for directions, blue for services, brown for recreation) rounds out a driver's understanding of the informational signs on the road.