The lead author is the first named author

Author

An author is broadly defined as "the person who originates or gives existence to anything" and that authorship determines responsibility for what is created. Narrowly defined, an author is the originator of any written work.-Legal significance:...

 of a publication

Publication

To publish is to make content available to the public. While specific use of the term may vary among countries, it is usually applied to text, images, or other audio-visual content on any medium, including paper or electronic publishing forms such as websites, e-books, Compact Discs and MP3s...

 - i.e. a research article or audit

Audit

The general definition of an audit is an evaluation of a person, organization, system, process, enterprise, project or product. The term most commonly refers to audits in accounting, but similar concepts also exist in project management, quality management, and energy conservation.- Accounting...

. The lead author is typically the person who carried out the majority of the research, and wrote and edited most of the manuscript. The list of trailing co-authors reflects, typically, diminishing contributions to the work reported in the manuscript.

Authorship standards vary widely across disciplines . The proportion of multi-author papers has increased in recent decades, reflecting increasingly complex multi-investigator research projects , as well as the "publish or perish" culture of academic performance evaluation.