Electronics - Standard Logic Devices (SLD) - Discussion

Surface-mount technology (SMT) is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD). Both technologies can be used on the same board for components not suited to surface mounting such as transformers and heat-sinked power semiconductors.

SMD Surface-mount devices (active, passive and electromechanical components)
SMT Surface-mount technology (assembling and mounting technology)
SMA Surface-mount assembly (module assembled with SMT)
SMC Surface-mount components (components for SMT)
SMP Surface-mount packages (SMD case forms)
SME Surface-mount equipment (SMT assembling machines)

Can anybody explain me that how SMT makes efficient use of printed circuit space?

SMT is nothing but the Surface Mount Technology.