In an effort to combat digital item theft, Steam is rolling out a new security measure called “trade holds”. This places item trades in a three-day hold to ensure authentication. Hit the jump to find out more.
In the FAQ section detailing trade holds, Steam explains that this feature protects accounts and the valuable items (lovely hats, for example) linked to them. The three-day buffer gives users a chance to verify their trade and make sure no one is craftily stealing their items. However, if you use the Steam Mobile Authenticator within seven days prior to the trade, then the trade is processed immediately. Furthermore, if you spot a trade in progress that you didn’t approve, it can be cancelled and your account will be placed in a “trading cooldown”. This will supposedly allow users to track down the breach in their security and prevent further compromises.
Source: Steam support