Logistics is the movement of goods or people for a specific purpose. It might be bringing goods to customers, moving troops in the military, but overall it is the coordination of bringing goods or people from one point to another. It can be very complicated, changing hands or types of travel many times.
When I was a buyer for Bloomingdale’s I was monitoring where my order was to track timing and make sure I would have what I needed when I needed it. If I had a big sale coming up, if I did not have the stock necessary for the promotion in time, I was going to have a big problem. If something was late shipping from the vendor, I might have to do an emergency drop shipment bypassing the usual distribution chain and ship directly to the store. That’s just an example.
USPS, UPS, DHL, are using logistics to get your package from you to the receiver. It might move by plane, then boat, then ground, then change to a local carrier, etc.