TIF

TIF or Time In Force is a property that indicates the life time of the order. 

TIFDescription
Immediate or Cancel (IOC)The order should be filled completely and immediately, otherwise it is cancelled. The trader can control the volume necessary for the order to execute. The volume necessary for the order to execute (other than the entire volume) can be adjusted in the Min Qty field that appears if you select IOC. 
Good till Market Close (Day)The order will last until the market closes for the day.
Good till Cancelled (GTC)The order will last until it is cancelled, which means that unless it is cancelled during the day, it will remain in the market for the next trading day.
Good till Time (GTT)The order will last until the time specified in the Time(Sys) field. The Time(Sys) field appears when you select GTT.
Fill or Kill (FOK)If FOK order is not filled when sent to the market it will be cancelled. The order should be filled completely by one or many trades, otherwise it is canceled.