Let's listen to Michael Willems, VA3MVW say.
Ham radio is really called amateur radio. But a better name would be amateur radio communications.
Radio transmission is regulated closely all over the world. You cannot just transmit: you generally need a license, and certain frequencies are reserved for certain uses. Otherwise a security guard’s walkie talkie or a taxi’s radio might interfere with airplane communications, or with cell phone calls, or with a gazillion other uses. So internationally, governments have agreed in great detail on what frequencies are uses by whom, for what.
And some frequencies are reserved for hobbyists, or amateurs, or “hams”. On these frequencies, radio amateurs who have passed a government exam and obtained a license can talk to other amateurs. Only talk, or morse code, or some other analog or digital modes are allowed. And only non commercial use. Sometimes,musing some frequencies, you talk to other amateurs locally, in the same town, say; and sometimes, using “shortwave” or “HF”, you can talk to distant amateurs. Sometimes even half way across the world.
Why? For fun. And to learn about radios and antennas and new communication technologies and the earth’s ionosphere.
Here is my “station”, VA3MVW ( that's my government-issued call sign):
You see that radio? It says 14195. Meaning a frequency of 14.195 MHz, and that's in one of those areas reserved by governments for radio amateurs. If I tuned that radio to, say, 16.195 MHz and pressed the transmit button, I would be breaking the law, and interfering with some other service.
Amateur radio is very handy in emergencies. When there’s a natural disaster, say, the phones will stop working, cell service fails, and theres no way to communicate. No way except amateur radio, that is.
So it can be useful. But above all, it's fun. It's fun to use my skills to have a brief conversation with someone in Brazil, or Morocco, or Finland. Without using the Internet, or the phone.