So far we have delved into some pretty heavy topics. We don't want the reader to feel overwhelmed so lets get back to the practical advice for a moment.
Again, I hope not to alienate the reader, but sometimes it is helpful to approach topics that may be considered as a given with fresh eyes.
What is an auction? An auction is a publicly advertised sale whereby single items or groups of associated artefacts are organised into 'Lots' to be sold. The price of each 'Lot' is not fixed but estimates are given by the auction house to guide the purchaser in deciding what an item may be worth. The guide price is usually given within a specified range in the Local currency of the saleroom (e.g. £150-200) and may also be given in other currencies if the sale is marketed internationally.
It may seem blindingly obvious, but a sale catalogue is a means of advertising. It is produced with the specific intention of marketing the lots in a given auction before the sale. The star item (usually the most valuable economically) is prominently advertised on the cover (Don't even think about bidding unless your name is George Ortiz or Sheikh Al-Thani).
The prime aim of the auction house is to sell the star item. Everything else is to a greater or lesser degree, secondary.
The more important items will be towards the front of the catalogue (i.e. single item lots) and lesser lots (i.e. low value multiples) wilbe pushed to the back, depending on sub-categories.
Auction catalogues may be specialist (i.e. dedicated to a single collection or type of object such as antiquities) or general. Usually specialist sales are held by major auction houses and general sales by provincial auctioneers.
After the sale, prices realised are published in a list of 'auction results'.
The auction house' conditions of sales are also provided in the sale catalogue and you will need to understand how the auction itself functions before bidding.