Wikipedia has this here, I find it appropriate: "String theory is a scientific theory that uses complicated mathematics and physics to try to explain how the universe works. It is usually agreed there are only four important forces in nature: - the force of gravity - the electromagnetic force - the strong nuclear force - the weak nuclear force String theory is an attempt to explain these four forces using one single theory (or unified field theory). This may also be a theory that can bring together other physics theories all at once. If the string theory is true, it is one of the few theories that could explain why there is gravity. It explains gravity through quantum mechanics. With traditional physics theories, this was not possible." "Usually, scientists think of matter as being made of very, very small particles. These particles are so small (we are talking on a scale much smaller than an atom) we cannot observe them to see their shape. Currently, all mathematical formulas assume they are point-like and therefore have no size at all. The main idea behind string theory is that this assumption is wrong, and that these small particles are instead shaped as tiny strings. The theory imagines that these strings are not precise particles (unlike things that are seen and counted). The strings are very small (10^-35 m long), yet they seem to behave like regular particles. It explains how other particles and forces behave. Because they are so small their actual shape doesn't matter much when we are doing calculations of bigger objects." Source and further information: http://simple.wikipedia.org/wiki/String_theory

I am the layman. I don't know the string theory. Please explain it to me. Then I will tell you how you explained it to me!

do you know, in most cases the average person either isnt interesed any way, or couldnt concieve what it was all about, so Id probably just say to them, its the possibility that there are more than 3 dimensions to time and life as we know, it , possibly up to 25 dimension, in fact, maybe even more ! :)

==========. I read what string theory acts in 11- D space. But if we don't know what 1+1 = 2 how can we know what 5+4 = 9 ? And if we don't know what is 4-D negative space ( 4-D positive Mincowski space ) how can we understand 11-D space ( String theory) ? ============ ========= Best wishes. Israel Sadovnik. / Socratus. http://www.socratus.com http://www.wbabin.net http://www.wbabin.net/comments/sadovnik.htm http://www.wbabin.net/physics/sadovnik.pdf

It began in 1907 when Minkowski tried to understand SRT using 4D space. All SRT’s particles live and act in this " 4-D negative continuum - Minkowski space " . SRT has only one space - “Minkowski space “ and the " Minkowski space " is home for SRT. But " Minkowski space " is an abstract theory and nobody knows what " Minkowski space " really is. ========= . =========== Poor young Einstein, reading Minkowski interpretation, said, that now he couldn’t understand his own theory. “ Einstein, you are right, it is difficult to understand SRT using 4D space. But it is possible using my 5D space" - said Kaluza in 1921. This theory was tested and found insufficient. "Well", said another mathematicians, - "maybe 6D, 7D, 8D, 9D spaces will explain it". And they had done it. But the doubts still remain. "OK", they say, "we have only one way to solve this problem. We must create more complex D spaces". And they do it, they use all their power, all their super intellects to solve this problem. Glory to these mathematicians !!!! But………. But there is one problem. To create new D space, mathematicians must add a new parameter. It is impossible to create new D space without a new parameter. And the mathematicians take this parameter arbitrarily (it fixed according to his opinion, not by objective rules). The physicist, R. Lipin explained this situation in such way: "Give me three parameters and I can fit an elephant. With four I can make him wiggle his trunk…" To this Lipin’s opinion it is possible to add: "with one more parameter the elephant will fly." The mathematicians sell and we buy these theories. Where are our brains? ==========.