In judicial foreclosure your lender will seek to force the sale of your property to pay off the loan through the court system. The lender will file a lawsuit against you seeking relief in the form of foreclosure of your property.
Judicial foreclosure, unlike non-judicial foreclosure, allows the lender (assuming you signed personally for the mortgage) to obtain a deficiency judgment against you in the event the sale of the house does not produce sufficient funds to pay off your loan obligation. Said another way, a deficiency judgment is an enforceable debt representing the difference between the balance of your loan and the amount received from your property at the foreclosure sale. This is not the case in states that follow the non-judicial foreclosure process.