users

Active users is a software performance metric that is commonly used to measure the level of engagement for a particular software product or object, by quantifying the number of active interactions from users or visitors within a relevant range of time (daily, weekly and monthly).
The metric has many uses in software management such as in social networking services, online games, or mobile apps, in web analytics such as in web apps, in commerce such as in online banking and in academia, such as in user behavior analytics and predictive analytics. Although having extensive uses in digital behavioural learning, prediction and reporting, it also has impacts on the privacy and security, and ethical factors should be considered thoroughly. It measures how many users visit or interact with the product or service over a given interval or period. However, there is no standard definition of this term, so comparison of the reporting between different providers of this metric is problematic. Also, most providers have the interest to show this number as high as possible, therefore defining even the most minimal interaction as "active". Still the number is a relevant metric to evaluate development of user interaction of a given provider.
This metric is commonly assessed per month as monthly active users (MAU), per week as weekly active users (WAU), per day as daily active users (DAU) and peak concurrent users (PCU).

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