I put in 10*10*10*100, and it said infinity?

The number is too huge to expess in any normal way.  BUT it is not infinity .

$${\mathtt{10}}{\mathtt{\,\times\,}}{\mathtt{10}}{\mathtt{\,\times\,}}{\mathtt{10}}{\mathtt{\,\times\,}}{\mathtt{100}} = {\mathtt{100\,000}}$$

Are you sure you didn't put 10^10^10^100

$${{\left({{\left({{\mathtt{10}}}^{{\mathtt{10}}}\right)}}^{{\mathtt{10}}}\right)}}^{{\mathtt{100}}} \approx \infty$$