I have a twin brother, who yes, is sadly one short minute older than me. It is something he never lets me forget. But I wouldn't have it any other way. And no, we are not identical.
Starting as soon as I could talk I was often asked what it was like to be a twin. However, the only response I had was "it's just like having any other sibling." Having no other siblings other than my brother, being a twin my entire life has felt normal since I simply have nothing else to compare it to. However, as I grew older, I learned that although it was normal to me, being a twin was something so incredibly special.
For starters, I have never had to experience that awkward moment of awkwardly standing while everyone sings "Happy Birthday" to you, at least not alone. It didn't take us long to figure out the best tactic was just to sing along and address it towards the other person.
At times it can be a lot- depending on various factors it can sometimes seem that you and your twin never get a minute apart, especially if you attend the same school and have the same group of friends. However, with enough time (and fights) you'll find a balance. However, you'll never hear the end of the questions asking if you can read minds, or whether or not you're identical.
Above all, however, possibly the best thing about having a twin is having someone who understands exactly what you're going through when you're going through it. They know the anxiety you're feeling before the first day of school or the excitement before the last. No matter what it is- they are going through it with you.
From before I was born I had a built-in best friend next to me. And although we've had our fair share of fighting, I wouldn't have it any other way.