Apache Hadoop is an open-source framework for reliable, scalable and distributed computing. It spreads very large data sets across a cluster of computers and processes them in parallel, which makes it a base for batch analytics and data pipelines. Organisations that want to run large-scale data processing themselves can use it instead of managed services such as Amazon EMR or Azure HDInsight. It is delivered as software installed on servers the organisation controls.
Hadoop is developed by the Apache Software Foundation, which describes itself as a U.S. 501(c)(3) charitable organisation, and is released under the Apache License 2.0. The foundation has no commercial owner, so the foreign-parent question that applies to vendor products does not arise for the project itself. Because the software is open source and runs on infrastructure the organisation controls, a European organisation can deploy it in an EU data centre and decide where its data is stored. Commercial Hadoop distributions come from separate companies whose ownership and hosting terms need separate review.