Log4Shell
Background
Background
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Log4j is an [open\-source](/wiki/Open_source "Open source") logging framework that allows [software developers](/wiki/Software_developers "Software developers") to [log](/wiki/Logging_%28software%29 "Logging (software)") data within their applications. This data can include user input. It is used ubiquitously in Java applications, especially enterprise software. Originally written in 2001 by Ceki Gülcü, it is now part of Apache Logging Services, a project of the [Apache Software Foundation](/wiki/Apache_Software_Foundation "Apache Software Foundation"). Tom Kellermann, a member of [President Obama](/wiki/Presidency_of_Barack_Obama "Presidency of Barack Obama")'s Commission on Cyber Security, described Apache as "one of the giant supports of a bridge that facilitates the connective tissue between the worlds of applications and computer environments".


Who wrote the original version of Log4j?