At Discrete Points in Time?

Discrete time views values of variables as occurring at distinct, separate "points in time", or equivalently as being unchanged throughout each non-zero region of time ("time period")—that is, time is viewed as a discrete variable. ... The number of measurements between any two time periods is finite.

Is time continuous or discrete?

Time is a continuous variable. You could turn age into a discrete variable and then you could count it. For example: A person's age in years.

What is discrete-time frequency?

A discrete signal can be a representation of a continuous time signal, measured at distinct time intervals. The time between each sample is called the sampling period, and the sampling frequency is then one over the sampling period. ... The frequency is then simply f = 1/N or 2*pi/N (in angular frequency, radians).