Wikipedia
ApacheCon
ApacheCon is a conference about the open source Apache HTTP server and related software, run by the Apache Software Foundation. It has been in existence since 2000, and has been held once or twice a year since then, usually in North America or Europe but sometimes in Asia. A typical size for the conference is 500 attendees, with 75% of attendees being developers.
In addition to Apache, the conference showcases technologies including Hadoop, Cassandra, Apache Spark, Apache Mesos, BigTop, CloudStack, Lucene, and Solr.
In 2015, discussions about Apache in the context of big data were split off into a separate event, Apache: Big Data.