Vellum41 is a general web directory organised as a reference archive. The catalogue holds 833 entries across 22 named sections, each representing a distinct field of commerce or public interest. Entries are drawn from a wide geographic range and are not restricted to any single industry, language, or region. The archive follows a simple classification principle: every entry is assigned to the most relevant specialist section, and anything that does not fit a named category is filed in the Open Accession Register. This approach keeps each section coherent while ensuring no submission is turned away for want of an appropriate category. Submissions are reviewed before admission. The catalogue does not require payment for listing, and there is no scoring or ranking applied to entries — each accession is recorded on equal terms. The review process exists to confirm that a site is active and broadly relevant to the selected section, not to evaluate quality or authority. Vellum41 takes its name from the prepared calfskin traditionally used for durable record-keeping — a material chosen by archivists when permanence and legibility mattered above all else. The name reflects the directory's commitment to maintaining a stable, accurate, and well-organised catalogue over time. This directory is maintained for researchers, professionals, and general visitors who need a structured reference rather than an algorithmic search result. The catalogue is updated as new submissions are received and pass review.