Accord to my knowledge of American English, people ask
What's you favorite TV show?
and it can refer to anything,even the nightly news.
Is this understanding correct?
Can TV program and/or TV series be used in the above sentence? If so, is there a change in meaning? That is, are the three terms always interchangeable? When might they not be interchangeable?
In your experience, does this usage represent any change over the years, say from the seventies to now?
Best Answer
They are not interchangeable. I almost never use or hear other people use the word 'program' to refer to a TV show. This might be a regional thing. (I live in the Midwest of the US.)
A TV show can refer to something like the news. However, you would not use "show" to refer to a special, or something that doesn't come on TV regularly.
A TV series would be any show that has seasons. (which in British-English are called 'series') A news show or late night show doesn't have seasons in the same way that a comedy show or something like American Idol does.