Qu'est-ce que « Point process, counting process » ?

A point process on $[0, \infty)$ is a random, locally finite set of event times $t_1 < t_2 < \dots$. Its counting process is $N_t = \#\{i : t_i \le t\}$, a right-continuous, integer-valued, nondecreasing adapted process with jumps of one.