¶ … job aid that reduces human error and lack of attention to detail by providing a list of policies, procedures, or items that are needed to produce a consistent job or product. There are checklists used in transportation to ensure the vehicles are ready, in clinical medical practice to organize charting and patient history, in software engineering to check process compliance and code, in litigation to deal with the complexity of discovery, in biology/science to list standardized practices and names, and even in everyday hobbies and life to organize materials, shopping, or contents. This tool of organization and operation may seem simple, but it provides a template and framework for innumerable tasks in almost endless ways (Gawande, 2007). It is interesting to note that this simple tool -- so logical and valuable, has saved so many lives in medical care (e.g. surgery, medication, etc.) by simply trying to understand a multistage process management tool. Can we even imagine the complexity of a modern jetliner or Space Shuttle without it? (Watcher, 2010). It seems the modern checklist is about 80 years old, and was derived from the complex nature of early aviation issues to avoid safety and mechanical errors....

For instance, what was needed was a way of making sure that everything was done prior to take off -- nothing was overlooked. Rather than relying on memory or experience, since human error and variables change rapidly, a systematic list (checklist) was used that became standard for the industry (Schamel, 2011).
One of the more complex scientific tools that was known as early as the late 1600s with Isaac Newton was called the Great Principle of Similitude As scientific theory progressed, this became the way that scientists described the dimensions of physical quality that were associated with mass, length, time, electric charge, and temperature -- as well as the abstract concept of dimension. This became known as dimensional analysis, and it is a tool that is used to find or even check relationships between physical qualities (mass) by using their dimension. It takes Newtonian mathematics and describes the physical laws that are independent of the unit to measure properties. This is particularly appropriate when we measure something that has different units. For instance, if we measure height, and we are told that someone is 16 tall. We then say, 16 inches (very short) 16 feet (very tall), etc. But…