Okay, you said to rewrite the question about Km and Vmax. Please make
the answer easier to understand. I want Km and Vmax easier to
understand. See if you can make real easy to understand. This is the
response to the question you  wanted me to restate. Please make the
answer really simlpe to understand.
                                Ted.

Note to Researchers:

This appears to be in reference to this question:

http://answers.google.com/answers/threadview?id=429901

First of all, Km and Vmax are properties that are used to describe the
kinetics of enzymes.  Simply stated Vmax is the is maximum rate (v) at
which an enzyme can convert substrate to product.  At this point the
active sites of all the enzymes are saturated with substrate, so
adding more substrate won't make the reaction go any faster.  Km, or
the Michaelis-Menten constant, is a dissociation constant.  Therefor,
it is the concentration of substrate at which 1/2 of the enzyme is
bound to substrate.  Likewise it is also the concentration of
substrate at which the reaction rate is 1/2 Vmax.  Typically Km is
used as a relative measure of the enzymes affinity for its substrate,
with a lower Km meaning that the enzyme likes to bind substrate
better.

Km more specifically is the rate at which the enzyme and substrate
disassociate (without forming a product) plus the rate at which they
dissasociate and form a product over the rate at which they enzyme and
substrate form the Enzyme-substrate complex.

You did say really simple to understand, so try this:

Vmax is the theoretical maximum rate of catalysis of the enzyme, if
all active sites were always occupied. It is impossible in practice,
but can be calculated from experimental data.
Km is basically a measure of the affinity of the enzyme for its
substrate. In practical terms, Km is the substrate concentration
required to reach 50% of Vmax.

I saw your other question, and these figures can be useful in protein
purification for determining the purity and quality of the enzyme you
have purified.