The Biographical Directory of the United States Congress is a biographical dictionary of all present and former members of the United States Congress and its predecessor, the Continental Congress. Also included are Delegates from territories and the District of Columbia and Resident Commissioners from the Philippines and Puerto Rico. 

The online edition also includes a guide to research collections (a list of institutions where member's papers, letters, correspondence, and other items are archived) as well as an extended bibliography of published works concerning the member (a shorter bibliography is included with the member's biography). These additional resources when available can be accessed via links on the left side of the member's page on the website. 

Charles Lanman, author, journalist, and former secretary to Daniel Webster, gathered the first collection of biographies of former and sitting members of Congress for his "Dictionary of Congress", published by J. B. Lippincott & Co. in 1859. Lanman intended his "Dictionary of the United States Congress" to serve primarily as a guide for sitting Members of Congress, much as the "Congressional Directory" functions today. 

In 1864, the House of Representatives and the Senate approved the publication of an updated version of Lanman's "Dictionary of Congress" by the recently established Government Printing Office. In the late 1860s Congress offered Benjamin Perley Poore, a journalist and clerk of the Senate Committee on Printing and Records, the job of preparing a "Congressional Directory" with biographical sketches and the kind of reference information found in the "Dictionary of Congress".
what does Charles Lanman do for a living?
Charles Lanman, author, journalist, and former secretary to Daniel Webster