CB Radios
Back before cell phones were a thing, many cars had a CB radio. These were a good enough way to communicate with other drivers on the road. Made popular in the ‘Smokey and the Bandit’ movies, the CB radio was a great piece of technology in vehicles. The only problems were that the technology was expensive at the time and not the most practical thing to have hanging in your muscle car (via Nostalgic Central).
CB Radios started to fade into obscurity in the 1990s. Part of the reason for this was the rise of car phones and cell phones in general. You didn’t need to have a CB radio when you could have an entire car phone built right in. Needless to say though, the CB radio was quite a popular option that paved the way for car phones.