Input different values for the cosmos and see how the Universe changes.
The data is divided up between the low redshift (velocity) supernovae and the high velocity supernova.  Click on those buttons to turn on/off that data.The horizontal axis (z) represents the redshift, or velocity of the objects, while the vertical axis (DM) is a measure of their distance.

Matter Density (Omega) is a measure of the mass density (kind of like the gravity) of the Universe.
Cosmological Constant (Lambda) measures the amount of "anti-gravity" or acceleration of the Universe.
The Hubble constant is, of course, the Hubble Constant.
Omega should be between 0 and 2, Lambda should be between 0 and 1, the Hubble Constant should be a reasonable value, probably somewhere between 55 and 75, the currently observed limits.

For a "flat" Universe, the value of Omega and Lambda should add up to 1.

To reset the values to their default settings, press the "Reload" button on your browser, while holding down the shift key (this is true for Netscape, I don't know what Internet Explorer does).