For many people, home is where they live and spend most of their time. For others, home is where they grew up. I'm just about to move house for the 5th time from somewhere I've lived for the last 6 years (the longest amount of time I've spent in one house) but I don't feel particularly attached to the place. I also went to a boarding school for 7 years of my life, which I regarded as my 'second home' - incidentally, I wonder where MPs regard as home...
Someone said to me, 'home is where your stuff is'. That's all very well except if you find yourself constantly travelling from place to place and living out of a suitcase! For many people home is where their family is, but that concept rather changes when your family is either separated or old enough to become spread out all over the place. When I'd finished my first year of university I was talking about going home for the summer and was told by a friend 'no, you're leaving home for the summer. You'll be back home in September!'
Maybe home isn't a fixed thing, nor does it have to be a single place at any one time. I think home is where you feel safe and comfortable. In the words of Simon and Garfunkel:
"Home, where my thought's escaping
Home, where my music's playing
Home, where my love lies waiting silently for me"