Ever since [[Updates#.2841.29_cea23d0:_Markets|Update 1.5.0]], the market is a way for us to trade between players and keep the economy and playing field diverse. For example, one might need [[gold]] for [[CPU]] production but doesn't want to produce gold. He can instead buy gold from another player who is creating excess gold, say because he has one CPU factory only but one gold mine actually would actually too much.
=== Selling prices ===
A good rule of thumb is to buy at about 1.4x for most products, 1.6x for VERY useful non-end products, and 1.2x for not-so-useful non-end products and end products (except for <$1 assets which are mostly $3).
If nobody else is selling, supply and demand should tell you to sell for more. Likewise, a massively overproduced item is NOT worth selling for the prices above. This ranges a span of about 1.2x extra on both sides.
==== Examples ====