In 1960 System International (SI units) unit was approved by the conference of weights and measures. It is an international organisation of which most of the Countries are the members. In this system also unit of linear measurement is metre. However, in this system use of centimetres and decametres are discouraged. Of course major difference between MKS and SI is in the use of unit of force. In MKS unit of force is kg-wt (which is commonly called as kg only) while in SI it is newton.
The recommended multipliers in SI units are given below
Giga unit = 1 × 109 units
Mega unit = 1 × 106 units
Kilo unit = 1 × 103 units
unit = 1 × 10 0 units
Milli unit = 1 × 10–3 unit
Micro unit = 1 × 10–6 unit
Commonly used linear units in surveying are kilometre, metre and millimetres. However centimetre is not yet fully given up.
For measuring angles sexagesimal system is used. In this system:
1 circumference = 360°
1 degree = 60′ (minutes of arc)
1 minute = 60″ (seconds of arc)
