If you mean on a contract that you need to pay (invoice), it probably has something like 2/10 net 30. If this is what you are talking about it means that you can take a 2% discount if it is paid within 10 days, otherwise the "net" amount is due in 30 days.
Net means.the amount of units squared will fit around a box with out over lapping and having enough for the sides to.
Performance bond A surety bond between two parties, insuring one party against loss if the terms of a contract are not fulfilled. Usually part of a construction contract or supply agreement.
The net of a cube is a 2 dimensional representation of it.
The mean, or the average.
The term mobilization, when used in construction bid, is the activation of a contractor's physical resources for transfer to a construction site. It also refers manpower until the completion of the contract.