NIST SP 800-191 and NIST SP 500-291 Ordinarily, I would not publish this document because it is so small (13 pages), and the printer won't print less than 24 pages. However, in this case I feel I need to make an exception because of the significance of the subject. Fog Computing, Edge Computing, and Mist Computing are three terms that will gain in importance as the Internet of Things reaches into every aspect of our daily life. I plan to also publish this on Kindle. I am including the NIST Cloud Computing Standards Roadmap (NIST SP 500-291) which includes an excellent definition of Cloud Computing as a counterpoint. Managing the data generated by Internet of Things (IoT) sensors is one of the biggest challenges faced when deploying an IoT system. Traditional cloud-based IoT systems are challenged by the large scale, heterogeneity, and high latency witnessed in some cloud ecosystems. One solution is to decentralize applications, management, and data analytics into the network itself using a distributed and federated compute model. This approach has become known as fog computing. This document presents a formal definition of fog and mist computing and how they relate to cloud-based computing models for IoT. This document further characterizes important properties and aspects of fog computing, including service models, deployment strategies, and provides a baseline of what fog computing is, and how it may be used.