What's the difference between a surface and a curve??

[tired solar]

I'm new to this topic. How do I think about it?

[reef gulch]

1. Ask your question and show the work you've done so far. If you've posted a screenshot of a question, specify which part you need help with.
2. Wait patiently for a helper to come along.
3. Once someone helps you, say thank you and close the thread with:

   +close
   

4. Feel free to nominate the person for helper of the week in #helper-nominations
5. Do not ping the mods, unless someone is breaking the rules.
6. If you're happy with the help you got here, and the server overall, you can contribute financially as well:

[analog socket]

A surface is 2D, a curve is 1D.

[tired solar]

Can you explain how is it 2d?

We need 3 coordinates to describe it, isn't it a 3d object?

[analog socket]

No, you need 3 coordinates to describe any point on it, but the surface itself is still 2-dimensional in the sense that it doesn't have thickness.

[tired solar]

aha!

[analog socket]

Like a curve is basically a line that's, y'know, curvy, a surface is a plane that's curvy.

[tired solar]

gotcha

so a sphere is 3-dimensional, but its surface is 2-dimensional

[analog socket]

Right.

Because the sphere includes the interior, the surface doesn't.

[tired solar]

i get it

thank you!!

[analog socket]

Actually, technically the sphere is the surface, and the surface + interior volume is called a ball.

[tired solar]

like the thin sheet that makes the ball is called sphere, and the whole thing is called a ball?

[analog socket]

The surface is a sphere, the solid is a ball.

[tired solar]

aha.

[tired solar]

+close