The documents are drawn primarily from a collection of 2.4 million rolls of microfilm containing photographic images of historical documents from 110 countries and principalities. The documents include census records, birth and death certificates, marriage licenses, military and property records, and other vital records maintained by local, state, and national governments.
Volunteers install free software on their home computers, download images from the site, type the data they read from the image via the software, and submit their work back to the site. The data is eventually made publicly and freely available at Family History Centers or at the FamilySearch website for use in genealogical and family history research. FamilySearch anticipates that the number of names and associated genealogical data indexed is expected to accelerate as more people volunteer to index.
In February 2012 beta versions of Indexing apps were released for both the Android and iOS operating systems to be used on these types of mobile devices. The mobile app complements the FamilySearch indexing program by allowing users to index snippets on the go. In December 2012 FamilySearch stopped allowing further downloads of these beta apps - citing the relative expense of creating the snippets to be indexed, the need to further automate the creation of the snippets, and the need for further development of the apps themselves.