There are many types of AI.
Type 1. The standard mellee AI's which are good for making AI that can build a varity of buildings and manage armys' in a normal mellee style map.
Type 2. The advanced AMAI* (name might be wrong) which is used to make stronger melee AI capable of using more advanced melee systems.
Type 3. The Solo hero AI which is used in RPGs, dotas, and Areans and is made only of triggers.
Type 4. Same as type 1 but has triggers to help cordnate and counter oponents like used in Blizard's monoliths.
Type 5. (Expermintal) A combo of types 3 and 4 which might be impossiable but will allow the use in unique style maps like battlefield 2, and rise of china.
Type 6. DUMB AI which is used to do stuff as simple as cast impale on a target every attack to something as complex as making a tower every [X] distance.
Type 7. Freehand AI which only uses triggers and is used to run advanced trigger created effects like in the mini games of many maps.
Theses are the basic types of AI I can think of and most maps can use atleast 1 type.
I might make a tutorial on how to make/use each type but that depends on time.
