Module Tutorial:

Yum Modules:   
 - classes
   - base
   - config
   - repos
   - pkgSack
   - package objects
   - rpmDB
   - tsInfo
 - setup
 - querying
 - transaction creation
 - downloading files
 - executing a transaction
 - resetting transaction

  
 - installation-related
   - simple update script

 - datamining/correlation
   - repo querying
   
   
- examples: 
  - repoclosure
  - repoquery
  - repotrack