Imperial/US length of 3 feet or 36 inches. In 1959 defined in terms of metric units as exactly 0.9144 meters. 1 international yard is exactly 0.9144 meters (SI base unit of length). 1 yd = 0.9144 m.
1 Pica:
1 pica is exactly 12 points. In SI units the size of a pica depends on how large a point is. A PostScript point is 1/72 inches, so 1 PostScript pica would be about 0.0042333 meters.