Desmos is a free, web-based calculator that will allow teachers and students alike to plot the graphs of functions, points, and more. There are also some classroom activities designed for educators.
If you sign up with an account, you can create pre-made calculators for students to use for a specific topic. For example, when my Precalculus students were exploring ellipses and other conic sections, I created an ellipse calculator that has sliders on it so that students can explore what happens as different parameters change.
Some basics to know:
Desmos plots points by using coordinate notation e.g. (x, y).
You can plot multiple points by separating them with commas e.g. (1, 2), (4, 11).
Desmos recognizes equations, solved for either Cartesian variable (x or y)
This allows for plotting of non-functions, such as x = y^2
Desmos can plot inequalities, and systems of inequalities
Desmos can plot tables of points
You can sign in with a google account or sign up for a new account through Desmos and save pre-made graphs to Google Drive or another storage spot. Desmos will also generate URLs to share.
With URLs, you can embed Desmos into other webpages or apps such as Office Mix.
You can import pictures into Desmos in order to try and model different phenomena, such as parabolic motion.
And much more!