OpenOlympiad
Concept 1 of 8Foundation
Video

Point, line, ray, segment

  • Point: a tiny dot, no size. Named with capital letters: A, B.
  • Line: straight path extending forever in BOTH directions. Notation: ↔AB or line ℓ.
  • Ray: starts at a point, extends forever in ONE direction. Like a torch beam. Notation: →AB.
  • Line segment: has two endpoints. Has a fixed length. Notation: AB̄.

Two lines either meet at exactly one point (intersecting) or never meet (parallel).

Example
On your ruler, the edge is a line segment (has ends). A number line conceptually extends forever — it's a line.
LineRaySegmentParallel lines →
💡 Tip:Line ↔ two arrows; Ray → one arrow; Segment — two dots.
Prefer a video? Open YouTube search for “point line ray segment class 6

🎯 Try it!

5 questions to check what you just read.

0 / 5
  1. Q1.Which has TWO endpoints?
  2. Q2.A ray has ___ endpoint(s):
  3. Q3.A line has:
  4. Q4.Two lines that never meet are:
  5. Q5.The edge of your ruler is a: