# Intro To Lines, Line Segments, And Rays | Geometry | Khan Academy

Let’s get familiar with the difference between lines, line segments, and rays. Hint: a ray is somewhere between a line and a line segment!

Practice this lesson yourself on KhanAcademy.org right now:

Watch the next lesson:

Missed the previous lesson?

Geometry on Khan Academy: We are surrounded by space. And that space contains lots of things. And these things have shapes. In geometry we are concerned with the nature of these shapes, how we define them, and what they teach us about the world at large–from math to architecture to biology to astronomy (and everything in between). Learning geometry is about more than just taking your medicine (“It’s good for you!”), it’s at the core of everything that exists–including you. Having said all that, some of the specific topics we’ll cover include angles, intersecting lines, right triangles, perimeter, area, volume, circles, triangles, quadrilaterals, analytic geometry, and geometric constructions. Wow. That’s a lot. To summarize: it’s difficult to imagine any area of math that is more widely used than geometry.

Subscribe to Khan Academy’s Geometry channel:

## 22 thoughts

Great video, thank you very much.

thank you so much, I am home schooled and your videos really helps me :/)

3. You Coup says:

this takes me all the way back. back in the day. the summer of 1969

4. Wendy Wert says:

Cool

5. Tom McLean says:

weeew

6. Jennifer Kontonasakis says:

From a home school mom with a 3rd grader, THANKS!!!! Perfect supplement to my lesson with her. 🙂

ur soooo smart

8. Vanilla Dazzle says:

I definitely didn’t learn this in elementary school. People really learn this in elementary?

9. NUMBEROCK Math Songs says:

What the heck is a NUMBER ROCK?
Is it hard like a rock, or hard like a rock band?

10. Sheshrao Aherkar says:

Which software do you use? Amazing Teaching and Basics.

11. amhsamie says:

Wait technically even a line has to start somewhere. It starts in the middle but just keeps going on forever? If I am not mistaken a line should start in the middle and that is what I think all the teachers are doing wrong so this is how a line should look The starting point being the o but still it has a start point.

12. XANDER HAGAN says:

/………. cooool

13. 75monmon says:

Thanks for helping my kids on line segmensts

14. Cherryl Aquino says:

thank you!!!! it help me because tomorrow is my exam

15. leah lyla says:

this helped me with my Homework

16. itz fluffy says:

thank you for my homework

17. victor cuevas says:

Yoooou’ve never seen a woman’s attitude :- that is a LINE

18. Jackie TM says:

Your the reason I am in honors

19. blanco blanco says:

okay… so there’s a class line, like we form in school. the whole class is already on it, we’re moving to another location. the line has a beginning and end. but since it’s moving, is it a line segment, a line or a ray? cause a line goes on forever but nobody else is hopping on. what is a moving line labeled as?

20. Kyle Crissler says:

I don’t understand how to measure a line segment ,can anybody possibly comment a link?

21. Yesmins World says:

Great job at explaining things! I have a test on this soon this really helped me understand this alot better! Keep up the awesome work!!

22. mao mao says:

oh!I didn’t know that.