Statistics tools should be easily understood and clear to the reader before going deeply into the reliability methods. The statistics tools themselves are not very interesting from a mathematic equations approach, but we will be dealing with them from a civil and structure engineering point of view. In reality, structural engineers are already using statistics in their calculation for concrete or steel structure design, but they don’t realize it as the statistics terms are hidden inside the codes and standard and design limits, in addition to using design factors for load and member capacity in order to facilitate use in traditional engineering design procedure.