Most ham radios can scan hundreds of frequencies including many that are outside of the ham bands. Why not try to use most of the available memory channels in your radios so that you have a better chance of hearing what is going on around you? This post offers some advice about how and why that might be a good idea.
This blog post explains the difference between simplex and duplex communication, as well as describes several different types of repeaters.
The basics of repeaters: how they function, the equipment involved and the rules that govern repeaters and repeater owners.