The Explanatory Supplement is the reference text to the public data products derived from data acquired by the European Space Agency’s Planck satellite during its mission. Although this document provides the user of the Planck data a three sided view over the mission - the hardware, the pipelines used in the processing of the data and the final data products - the main purpose of this document is to describe the data products made public in the 1st Planck data release. Given the number and diversity of products made available in this release, the descriptions offered here for each product are not always exhaustive but they try to cover in every case the most immediate needs of the average user: what does a product consist of; what are the limitations and caveats for each product; what is the format of each data file. On top of this basic information the user is also offered a summary of the production process for each product. For details, users are advised to consult the Planck papers accompanying the data release.
Given the format this document is provided to the scientific community, a wiki, we will perform updates of its contents every time products are updated or added, every time more information becomes available and at every major data release.