One trading pit attribute which hasn't likely been seen in a long time and may never even be seen again is the 'fast market' designation. In looking for the official exchange definition and rules of a fast market, I was unable to to find it but here is the CFTC's definition from their webpage:
Fast Market: An open outcry market situation in which transactions in the pit or ring take place in such volume and with such rapidity that price reporters fall behind with price quotations, label each quote "FAST" and show a range of prices. Also called a fast tape.
Certain rules applied during fast markets and one I remember is that the broker holding a limit order wasn't held liable for missing the trade if someone else traded through that price, i.e. Broker A has a price limit of 50 but the market prints 48 and market is now 52 bid but because it was a fast market Broker A doesn't have to guarantee a fill for the customer who was 50 bid. Having never been a broker, I'm not entirely sure that is how it works but vaguely from what I remember.
Another thing about fast markets is that I'm unsure as to who exactly classifies it to be one, my guess is it's the pit committee (of traders/brokers) along w/the pit reporter/supervisor. When a fast market is designated, we'd see FAST upon the exchange wallboards (as I tried to illustrate above) and prices skipping all over the place rather than their usual linear movement.
Globex handles orders at a sub-5 millisecond response time which makes the 'fast markets' of the past look incredibly slow by comparison.
