  In economics, there are many ways to describe the interaction between a
"seller" and a "buyer". The most common one, with which we interact almost
every day, is selling for a fixed price. This option is perfect for selling a
mass product, when we have a number of sellers and many buyers, and the price
for the product varies depending on the conditions of the relationship between
supply and demand. Another situation meets us already in markets, where a
product can be either mass-produced or more unique, so this option is already
closer to the object of our discussion.However, a one-on-one transaction is a
much more unstable option, which is why it is also more difficult to model,
since it is determined not so much by algorithms as by psychology and the
difference in the bargaining ability of the two parties. An even closer example
of an auction is price discrimination, when the price for the buyer is
determined not only by supply and demand, but also by which group the buyer
belongs to. But in this case, the product is not unique, and the final seller
is the only one. Thus, we have identified the main auction criteria and their
features of the "game".
