Is this a known probability distribution: $p(x;\theta) = \theta(1-\theta)^x$ for $x=0,1,2,...$

Question

I'm given a set of random variables where each $X_i$ has distribution:

$p(x_i;\theta) = \theta(1-\theta)^{x_i}$ for $x=0,1,2,...$

I need to compute the expectation $E(\sum_{i=1}^n X_i)$.

Is the distribution of $X_i$ something known?

I cannot recognize as a well known distribution.

Thanks in advance.