I think the saying "one person's trash is another person's treasure" helps answer this question. Trash more often has the meaning of something discarded, whereas garbage more often carries the meaning of true refuse, often food waste. Of course, food waste can be a treasure to a gardener working on a compost pile, but I'm speaking generally here. It's not a very significant distinction, and the terms are often used interchangeably, but there are instances when they are not synonymous.
There was a little note stuck to the can. It said, in essence, that my refuse hadn't been picked up because -- and I quote -- ''trash and garbage had been mixed.''
I hate making mistakes like that. I didn't close the cover on a book of matches before striking. It was weeks before I got over the guilt.
I called Georgia Waste Systems, where I have my trash/garbage account, to apologize. They were very nice and said a lot of people make the same mistake I did and they were not planning a lawsuit.
As long as I had somebody on the phone who could explain, I asked, ''What is the difference between trash and garbage?''
''Garbage,'' the woman said, ''are things that come from the bathroom or kitchen.''
''You mean like bread you leave out for months and green things start growing on it?'' I asked.
''Precisely,'' she said.
''Trash,'' she continued, ''is basically anything else. We do not pick up leaves, for instance, or old furniture or boxes of materials that were collected when somebody cleaned out their attic.''
Best Answer
While the two terms are sometimes interchangeable, I would say that the usage would differ depending on the shape and purpose of the item in question.
A flag would typically be square or slightly oblong, as with the national flags of most countries. A banner tends to be more elongated, for example as you might see hung across a street during a parade. Flags tend to be attached by one side to a pole, whereas banners are typically attached at both ends, either fixed or on two poles. Furthermore, flags usually carry representative symbols or colours (e.g., chequered flag), whereas banners generally carry written messages (e.g., Happy Birthday Joe!)
On this basis few English speakers would refer to, say, the Union Jack as a banner. Likewise, Happy Birthday Joe! would not be called a flag.