1.  Surfactants are "Surface Active Agents"

2.  Surfactants are Emulsion Agents

3. Surfactants Reduce Surface Tension

Surfactant stands for Surface Active Agent.

At right is a diagram depicting a surfactant.  A surfactant is made up of two parts, a head and a tail, which exhibit differing properties; the head is hydrophilic (it is attracted to water), while the tail is hydrophobic (it tends to distance itself from water).  It can be said that a surfactant has a "split personality,"  because it is composed of two parts with entirely different tendencies.  Because of these characteristics, a surfactant exhibits a unique reaction when it is put in water. 

Now, if one were to insert a surfactant in water (depicted by the number 1), it would rise to the surface (2).  It would be most "comfortable" with its head (the "water liking" part) submerged in the water and the tail (water "disliking" part) sticking out- into the air.  This is where the term Surface Active Agent originates. 

An Emulsion Agent is something that brings two things together that do not come together, under normal circumstances.  If one were to place oil and water in a beaker, the two wouldn't come together but remain as two individual solutions- not as a homogenous mixture.

When a surfactant is introduced to a beaker with oil and water, it links the two substances, and they form a homogenous mixture.  This property accounts for the fact that surfactants are found in soaps and detergents.

Surface Tension is a phenomenon that is found on the interface (where water and air meet) of water. 

Water normally dips down at the interface.  To explain this, let's chose two random water molecules.  Number 1 (above) is a water molecule somewhere in the beaker, and it is surrounded by other water molecules.  Molecules often are attracted two or repelled from one another- this force is known as cohesion.  Water molecule number one is being pulled in all directions by other molecules.  These forces are cancelled out by one-another, as a pull up is being negated by a pull down, etc.  Now, if we look at water molecule number two, it is also being pulled by other water molecules.  Yet, the pulls downward (by the water) are much greater than the pulls the air has on the molecule, and, as a result, the molecules by the air are pulled downward, slightly. 
      When surfactants are added to water, they rush to the surface because of property number 1 (they are surface active agents).  When the surfactants are at the surface, they offer a greater pull than the air does.  As a result, the dip is lessened and so is surface tension