File format is a standard way of encoding information so that it can
be stored in a computer file. Digital research data may be stored in a
wide variety of file formats, depending on the devices and tools used in
data collection and processing.
File formats may be proprietary (the encoding-scheme is designed and
owned by a company or organisation, and is not published, due to which
files can be opened only by those who have particular software or
hardware tools) and/or prone to obsolescence (legacy formats, bit rot).
To ensure that users can access and understand data and that data can
be preserved in the long term, it is necessary to use open (defined by an openly published
specification that anyone can use) and lossless formats (ensuring that
no data or quality loss will occur during file manipulation).
Some file formats, though proprietary, have become the de facto
standard due to their ubiquity (e.g. TIFF).