Types of Angles: Angles are classified by sizeâ€”acute ($<$90Â°), right (90Â°), obtuse (90Â°â€“180Â°), straight (180Â°), reflex (180Â°â€“360Â°), and full angle (360Â°).

Measuring Angles with a Protractor: Align the protractor’s centre with the vertex and the zero line with one arm. Read where the other arm crosses the scale; use the smaller number for acute angles and the larger for obtuse angles.

Constructing Angles Over 180Â°: For angles like 210Â°, draw the smaller internal angle (e.g., 150Â°), with the area outside forming the desired angle.