Membership Levels, Badges and Custom Titles
Users have a badge and, sometimes, a custom title, set by a moderator.
Contributor - Under the old Head-Fi, they paid a sum to not have to see the advertising for a year, along with other benefits. Paid contribution is currently unavailable.
Headphoneus Supremus - Has made more than 1500 posts.
Industry Insider - A top-level sponsor.
Others have "Sponsor" and the name of their company as a custom title.
Some users, for fun, were given custom titles. However, there are two custom titles which are important:
Sponsor - A Member of the Trade who has fewer restrictions as to where or what they can post as a result of paying for sponsorship.
Member of the Trade - A person who has a financial interest of some kind in an audio-related business and is subject to addition rules in the Terms of Service. MOTs cannot post without being tagged so that people are aware of their affiliation. If you find someone clearly from a company posting, please report one of their posts so we can tag them.