The state borrows money by issuing general obligation bonds, revenue dedicated bonds, or commercial paper. General obligation bonds must be approved by the voters, are backed by the full faith and credit of the state, and are generally repaid from unrestricted revenue sources. General obligation bonds include debt issued for recreation and environmental protection and school loans.  Revenue dedicated bonds typically finance specific projects with the stipulation that repayment will come from designated revenue sources. Revenue dedicated bonds include debt issued for transportation projects and debt issued by the State Building Authority for the construction of state projects, certain equipment financing, and higher education related projects.  Revenue dedicated bonds also include debt issued by the Michigan Tobacco Settlement Finance Authority for economic revitalization.  Commercial paper is used when short-term borrowing is necessary and is generally repaid from the proceeds of a bond sale.