The degree (°) is the most common unit for measuring angles, dividing a full circle into 360 equal parts. From navigation and construction to everyday geometry, degrees are the default angular unit worldwide. One degree equals π/180 radians or about 0.01745 radians.

The arcsecond (″) equals 1/3,600 of a degree, providing extremely fine angular resolution for astronomy, optics, and satellite imaging. The Hubble Space Telescope has a resolution of about 0.05 arcseconds, and stellar parallax measurements use milliarcsecond precision. One arcsecond equals 1/3600 degree or about 0.00000485 radians.