“Hams” can talk around the world, use (our own!) satellites, send television pictures, do computer-to-computer communications over-the-air, and more.
Usually “hams” are having fun — competing against each other in on-air contests, trying to talk to as many different countries – or states, or US counties, or islands, etc. – as they can for various operating awards, building or modifying antennas and radios, making new friends all over the world, or just chatting with old friends. This is the “hobby” aspect of Amateur Radio.
But when disaster strikes — earthquakes, hurricanes, floods, wildfires, etc. —radio amateurs are quick to offer their expertise, experience, equipment, and, most of all, time to provide emergency communications when normal means of communications are inoperative, unavailable or overloaded. No matter what it takes, “hams” will find a way to get the message through. Hams also provide communications for a variety of public events such as marathons, bike races, walk-a-thons, “buggy” races, etc.) And this is all as volunteers, for it is in fact illegal to accept compensation for communications via Amateur Radio. (FCC rules in the USA, may differ in other jurisdictions.) This is part of the “service” aspect of Amateur Radio.
You can find a more in-depth, illustrated explanation of Amateur Radio on the ARRL’s web site.
Here are some things I’ve written that are amatuer radio related: