To me, culture is usually something on a national scale. The common beliefs in a nation, the cuisine, national practices and celebrations, the lifestyle. Although I often find myself wondering if such a thing really exists any more in the modern world; at least for my country.
When I think of England, all I think of are football fans and eating kebabs after a night out on the lash. Neither of which I'm very interested in. Maybe I've become so accustomed to every other part of my culture that I just take it for granted now, and it takes an outsider to truly notice every part of the culture. For me personally, I don't really partake in anything that could be seen as 'British'. These days everything is just so multicultural; the meals I eat are usually Italian or Chinese, I enjoy media from across the world, and I have no love for Britain. In my eyes, there are so many different aspects of so many different cultures are now at our grasp that we just pick and choose whatever we want.
Although, I think this could really apply to many western nations. I've been to France and Germany and I see the same stores, brands, food (mostly) and celebrities (nearly all American). It really seems that so much traditional culture has died out after Americanisation and the development of a multicultural society; maybe that is the modern culture of the western world? I think that maybe countries in Eastern Europe, Asia, Africa and maybe South America retain a distinct culture; but I couldn't say for sure because I've never been to any of them.
Americans I have spoken to seem to think England is all about afternoon tea and biscuits, talking like a nobleman, being polite and respecting the Queen. I think they're about 100 years too late.
Subcultures are an entirely different kettle of fish, and I've never been a part of one so I don't really have much to say on the matter.