The Socrata Open Data API allows you to programmatically access a wealth of open data resources from governments, non-profits, and NGOs around the world.
The OpenAQ Community harmonizes disparate air quality data from across the world so that citizens and organizations can fight air inequality more efficiently. The data is captured from multiple sources and made accessible to all through our open-source platform.
Bulk upload: https://upload.openaq.org/
A collective list of free APIs for use in software and web development.
A Creative Commons handbook that teaches the legal, social, and technical aspects of open data. Teaches not only what you can do with an open data set, but how to go about getting datasets opened to analysis. If you're looking for a hands-on nitty-gritty book about mining open data, however, this isn't it.
CKAN is open source data management portal software for extremely large data sets, on the scale of entire governments. Used to publish, curate, share, search, and find datasets of just about any kind. Does visualization and metrics. Source code on Github (https://github.com/ckan/ckan). Written in Python, uses Postgres as its back end. Can interface with Apache Solr for search and indexing.
The datarefuge website. Probably as official as it's going to get. Has some useful definitions, at least. opendata Also has a bunch of rescued datasets available for download. data
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