Hi Bunny,
This is the same link I put in another post in this thread.
Science@NASA
As you can tell from the below example of text from the site, its dumbed down for simpletons like me.
"If the Moon were slightly smaller than the Sun, the best eclipses would be annular ones with no dramatic corona or blackening of the daytime sky. If the Moon were slightly larger, the full glory of the chromosphere and prominences surrounded by the glowing corona would be lost. Fortunately, the Moon is "just right." "
stu