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What is GitHub??

READ-ONLY SITE MATERIALS: Historical voting TWiki site (2015-2020) ARCHIVED from

The CDF specifications are stored on and made available to the public via “GitHub repositories.” You may be wondering, what the heck is that??? GitHub has gained a great deal of popularity in recent years, but why it is used can be confusing.

Fortunately, for most individuals who just want to view or download CDF specification material, the GitHub repositories can be thought of as simple websites. There is a README file displayed at each repository that should describe the contents of the repository as well as other related information, and one can download files just as with other websites.

A fuller explanation is that we are using GitHub repositories to store and make available and permit easier commenting on various versions of CDF specifications, including the documentation, the UML models, the XML or JSON schemas, and other items such as example files or validation tools. Each CDF specification has its own GitHub repository, one per specification. For example, the repository for the NIST SP 1500-100 CDF for Election Results Reporting Specification is

and the web-based version of the documentation is located at a NIST website linked to the repository:

The name “GitHub” comes from “git”, which is a tool used for version control of software.

So, why use GitHub repositories? There are a number of good reasons:

  • NIST and collaborators can store various versions of CDF specifications on the repositories and make them available in a variety of ways such as publicly for completed specifications or privately to collaborators for specifications in progress.
  • Anyone can comment on aspects of the material by using the “Issues” feature on the repository and their comments are thus tracked and easy for others to see and respond to.
  • Changes can be made in a controlled and organized way even when multiple people or organizations are involved at the same time.

More information about GitHub is widely available from Wikipedia and other sources.

Voting TWiki Archive (2015-2020): read-only, archived wiki site, National Institute of Standards and Technology (NIST)


This page, and related pages, represent archived materials (pages, documents, links, and content) that were produced and/or provided by members of public working groups engaged in collaborative activities to support the development of the Voluntary Voting System Guidelines (VVSG) 2.0. These TWiki activities began in 2015 and continued until early 2020. During that time period, this content was hosted on a Voting TWiki site. That TWiki site was decommissioned in 2020 due to technology migration needs. The TWiki activities that generated this content ceased to operate actively through the TWiki at the time the draft VVSG 2.0 was released, in February of 2020. The historical pages and documents produced there have been archived now in read-only, static form.

  • The archived materials of this TWiki (including pages, documents, links, content) are provided for historical purposes only.
  • They are not actively maintained.
  • They are provided "as is" as a public service.
  • They represent the "work in progress" efforts of a community of volunteer members of public working groups collaborating from late 2015 to February of 2020.
  • These archived materials do not necessarily represent official or peer-reviewed NIST documents nor do they necessarily represent official views or statements of NIST.
  • Unless otherwise stated these materials should be treated as historical, pre-decisional, artifacts of public working group activities only.
  • NIST does not warrant or make any representations regarding the correctness, accuracy, reliability or usefulness of the archived materials.


This wiki was a collaborative website. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these archived TWiki materials. Further, NIST does not endorse any commercial products that may be mentioned in these materials. Archived material on this TWiki site is made available to interested parties for informational and research purposes. Materials were contributed by Participants with the understanding that all contributed material would be publicly available.  Contributions were made by Participants with the understanding that that no copyright or patent right shall be deemed to have been waived by such contribution or disclosure. Any data or information provided is for illustrative purposes only, and does not imply a validation of results by NIST. By selecting external links, users of these materials will be leaving NIST webspace. Links to other websites were provided because they may have information that would be of interest to readers of this TWiki. No inferences should be drawn on account of other sites being referenced, or not referenced, from this page or these materials. There may be other websites or references that are more appropriate for a particular reader's purpose.


Created August 28, 2020, Updated February 5, 2021