Data exhaust refers to the data generated as trails or information byproducts resulting from all digital or online activities. These consist of storable choices, actions and preferences such as log files, cookies, temporary files and even information that is generated for every process or transaction done digitally. This data can be very revealing about an individual, so it is very valuable to researchers and especially to marketers and business entities.
Techopedia explains Data Exhaust
Data exhaust refers to all of the related data generated by digital activities, and this data tells a good story about habits and preferences. Data exhaust consists of virtual trails left behind, similar to the exhaust from a vehicle, a byproduct that reveals the trail it has taken. This data is used to target advertisements to specific demographics and for market research, which tells businesses the online preferences, behaviors and habits of potential customers, giving them insight into how to mold their business into something that the people will consume. This is called behavioral targeting.
In more legitimate science, this can be used to improve digital and online processes based on the behaviors of users. We can look for shortcuts to minimize required actions and find areas to optimize, improve or change outright. Data exhaust is widely used in data mining and big data analytics.