Hello I am in canada and I would like to know if the cb is still the most common type of radio on the road thanks for your answer.
Here in the US, I've had CB, ham and GMRS radios in my truck in the past.
By FAR, the most traffic I've heard were on the FRS frequencies.
CB is popular in some areas for some applications by some people. In my experience driving through the Western USA And Western provinces, CB is very quiet and no where near what it was like in the 1970's/1980's.
Ham radio can have some traffic, but it's rare, and will entirely depend on where you are.
I've heard a LOT of people on the highway using FRS. Yes, short range, but there's often enough traffic that you'll hear something frequently on the busier interstates. I was driving across California and Nevada earlier this year. I took a break on the side of the road. I had several radios running. By far there was more traffic on FRS than anything else.
Your experience will vary depending on exactly where you are. There is no right or wrong answer. It's about finding what works for you in your area.