Open data is information that is available for anyone to use, for any purpose, at no cost (definition by The Open Data Institute). In the words of the Open Definition, open data is defined as data that "can be freely used, modified, and shared by anyone for any purpose".
Open data has to have a license that says it is open data.
Without a license, the data can't be reused. In most jurisdictions there are intellectual property rights in data that prevent third-parties from using, reusing and redistributing data without explicit permission. Applying a license is important, even in places where the existence of rights is uncertain.
A dataset is open when satisfies the following requirements in its distribution: open license, access, open format. Publishing data in a machine-readable format does not necessarily make it reusable. In particular, if the machine-readable format is a proprietary format that is only readable when using proprietary software from a single vendor, particularly if it cannot be easily exported to other formats, then it is not practically re-usable. Formats defined by open standards are: CSV, XML, JSON and RDF, where there is good availability of open source tooling, such as readers, parsers and converters, for processing the data.
Open data is generating a great deal of excitement for its potential to empower citizens, change how government works, and improve the delivery of public services. It may also generate significant economic value, according to the McKinsey report "Open data: Unlocking innovation and performance with liquid information" released in 2013. According to the GovLab Index over 1 million datasets have been released by governments around the world last year.
Finodex gives you the opportunity to generate value and develop your business by making use of open data. It's the Future Internet Accelerator open to any business that uses open data as part of their products, services, building upon FIWARE technologies.