bid and ask

A price mechanism or market-based mechanism is any of a wide variety ways to match up buyers and sellers.Generally speaking, when two parties wish to engage in a trade, the purchaser will announce the highest price he is willing to pay (Bid price) and seller will announce the lowest price he is willing to accept (Ask price).The main advantage of such methods is that conditions are laid out in advance and transactions can proceed with no further permission or authorization from any participant. When any bid and ask pair are compatible, a transaction occurs, in most cases automatically.
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