Probabalistic Polynomial-time Algorithms & One-way functions I've been reading up on probabilistic polynomial-time algorithms and one-way functions, and I was hoping to get some guidance on the topic.

A textbook I'm reading states the following for one of the conditions for one-way functions:

Hard to invert: For every probabilistic polynomial-time inverting algorithm A, there exists a negligible function negl such that
$$Pr[A(f(x))\in f^{-1}(f(x))] \leq negl(n)$$
where the probability is taken over the uniform choice of x in $\{0,1\}^n$ and random coin tosses of A.

What exactly does it mean by "random coin tosses of A"? Is it stating that the "inversion function" is randomly generated by such a process?
A probabilistic algorithm uses random numbers to define the next step it should do (google for instance "Monte Carlo Algorithm").
"Random coin tosses" merely says that the random numbers are equally distributed.
The algorithm A will use the random numbers only internally, it will not output any random number. 
But A's output will depend on those random numbers.
Therefore, it will output a correct pre-image only with a certain probability.