Committers are individuals who have write access to a project’s source code repository. They may make changes to the project code and website directly, although they are expected to follow that project’s development guidelines when doing so.
At the ASF, a committer’s formal relationship begins when they sign an Individual Contributor License Agreement (ICLA). This is a legal document that defines the terms under which committers submit code to the ASF, granting the ASF and users of it’s software the necessary copyright and patent rights to use your contributions.
Committers must ensure that they are authorized to sign the ICLA; many employers will ask to review the ICLA before having you sign it, and depending on the employer and type of contribution you plan to make, your employer may need to sign either a Software Grant or a Corporate Contributor License Agreement (sometimes called a CCLA).