I believe the answer is: naturalistic observation
Naturalistic observation is being done without any form of variable manipulation from the researchers. The purpose of such observation is to make the result of the study represent the actual condition as close as possible. Usually only applicable for qualitative data.
This would be a perfect example of the system of barter as you are trading one book for the other. You can see from here what barter is, a trading system which involves direct exchange of goods without some kind of medium of exchange, for example money. Services can also be traded this way.
Answer:
The answer is the digital divide.
Explanation:
This concept refers to the unequal distribution of digital technology among different groups. Some criteria include their geography and class satatus. The digital divide mostly occurs due to the high expenses of acquiring said technology.
Although initially the phenomenon was seen as a matter of <em>having</em> the technology, today is considers access and usage.
