**Point:** A point has no length, breadth and thickness i.e., it has no magnitude. It has position only. It is regarded as an entity of zero dimensions. A point is always named with capital letters.

**Line:** A line has only length and no breadth or thickness. It is regarded as an entity of one dimension.

**Straight line:** A straight line is the shortest distance between two given points.

**Curve line:** A curved line is nowhere straight. There are endless varieties of curved lines.

**Horizontal line:** A horizontal line is perfectly level.

**Vertical line:** A vertical line is perfectly upright, like a plumb line.

**Oblique line:** An oblique line is neither horizontal nor vertical.

**Parallel lines:** Parallel lines are lines in the same direction. They cannot meet however far they may be produced.

**Ray:** A ray is a portion of a line that begins at some point. A ray has one end point.

**Line segment:** A line segment is a portion of a line. A line segment has two end points.