What do the sum of the reciprocal of n squared make if n is a natural number?

I’ve recently found out that $sum_{n=1}^{infty}frac{1}{n^2+n}$ makes 1, since it becomes $frac{1}{2}, frac{2}{3}$ and so on. After then, I’ve became curious if I do the same thing with the reciprocal of n squared, or $$sum_{n=1}^{infty} frac{1}{n^2}$$ I couldn’t find out the answer. Their sums don’t make a neat form like $frac{a}{a+1}$. Could anyone tell me what it approaches to?