Surface-mount technology

SMD capacitors and two through-hole capacitors (with long leads).

SMD resistors next to a match head

Surface-mount technology (SMT) uses electronic devices that are made to be placed directly onto the surface of printed circuit boards (PCBs).

Examples of surface-mount devices are resistors, capacitors, LEDs and integrated circuits. Surface mounted devices are generally smaller than those used in the older through-hole technology, which need longer leads and holes in the circuit board.

Surface-mount Technology Media

Surface-mount components on a USB flash drive's circuit board. The small rectangular chips with numbers are resistors, while the unmarked small rectangular chips are capacitors. The capacitors and resistors pictured are 0603 (1608 metric) package sizes, along with a very slightly larger 0805 (2012 metric) ferrite bead.
Surface-mount capacitor
Assembly line with pick-and-place machines
PCB assembly line: pick-and-place machine followed by an SMT soldering oven
SMD resistors in original packaging - this packaging allows for use in a mounting machine
Removal of surface-mount device using soldering tweezers
Example of component sizes, metric and imperial codes for two-terminal packages and comparison included

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