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= Manual

Apache Log4j is a versatile, industrial-grade Java logging framework composed of an API, its implementation,  and components to assist the deployment for various use cases.
The project is actively maintained by a {logging-services-url}/team-list.html[team] of volunteers and {logging-services-url}/support[support]ed by a big community.

Logging is an essential part of the software development process. 
It provides a way to track the flow of execution in a program, allowing developers 
to understand the application's behavior without needing a debugger. 
This is particularly useful when tracking bugs or understanding why a particular code runs slowly.

The original concept for Log4j was conceived in early 1996 when the 
E.U. SEMPER project decided to develop its own tracing API. 
In 2003, the project was donated to the Apache Software Foundation, which became Apache Log4j. 

Since then, Log4j has seen numerous releases and has become a widely adopted solution.

== When should you use Log4j?

Log4j is an excellent choice for any Java application that needs logging capabilities. 
It is user-friendly, fast, and flexible. You can use it to log messages at 
different levels of severity, from debug to fatal, and you can configure it to 
log messages to various destinations, such as files, databases, or the console.
See xref:manual/getting-started.adoc[] for an introduction.

== When not to use Log4j?

While Log4j is a highly suitable choice for many applications, 
it may be challenging to locate the information you require when 
logging a high volume of messages. 
Additionally, logging can impact your application's performance.

Log4j offers solutions to address these concerns. However, if you are in 
a unique situation where you are concerned about logging overhead or volume, you may wish 
to consider not using logging at all.

== What does Log4j offer?

Log4j offers numerous features, including:

include::partial$log4j-features.adoc[]

== How to learn more?

* xref:manual/getting-started.adoc[How can I get started with Log4j?]
* xref:manual/installation.adoc[How can I install Log4j?]
* xref:manual/configuration.adoc[How can I configure Log4j?]
* xref:manual/api.adoc[How can I use Log4j API?]
* xref:manual/performance.adoc[How can I tune my Log4j setup for performance?]
* xref:migrate-from-log4j1.adoc[How can I migrate from Log4j 1 to Log4j 2]?
* xref:manual/plugins.adoc[What are Log4j plugins] and xref:manual/extending.adoc[how can I use them to extend Log4j?]
