The clerk of the House is a permanent official of the House of Commons who advises the Speaker and MPs on the rules, practice and procedures of the House.
The clerk sits at the table of the House, immediately below the Speaker's chair.
He or she has a number of formal functions, such as taking minutes of the decisions and proceedings of the Commons, signing Orders and reading out the Titles of Bills, and also overseeing the administration of the House.
The clerk has an official residence in the Palace of Westminster.
When at the Table of the House the clerk wears black robes and a wig.
Lace trimmings complete the look on state occasions.
The equivalent in the Lords is called the clerk of the Parliaments.
The most famous clerk of the House was Sir Thomas Erskine May (1871-86) who wrote the Parliamentary bible, Parliamentary Practice, which bears his name.