Degrees and minutes
In a full circle there are 360 degrees. A degree is denoted by °, e.g. 360°.
Each degree is split up into 60 parts called minutes (of arc), each part being 1/60 of a degree. A minute is denoted by ', e.g. 1°= 60'.
Each minute is split up into 60 parts, each part being 1/60 of a minute called seconds (of arc). A second is denoted by '', e.g. 1°= 60×60 = 3600 seconds = 3600''.
Sometimes it is needed to convert the measure of the angle that is written as a decimal number into degrees and minutes, e.g 40.5 degrees. This is 40°+0.5×60' = 40° 30'
Radians
The circumference of a circle is 2πr. Based on this we set that 2π(rad) is equivalent to 360° and one π(rad) is equivalent to 180°. A radian is about $360/{2π}$ or 57.3 degrees.