Commonly abbreviated to AH Cliches (no accent on the e because we're a bunch of lazy francophobes), these describe certain concepts, technologies, events and scenarios that tend to crop up in a large number of timelines, particularly those written by those unfamiliar with the wider AH community. What follows is an alphabetical list of the most notorious clichés. As you can no doubt see, most of the clichés on the list have their own separate pages (which contain more info, with frequently tongue-in-cheek descriptions - just a precaution to keep you impatient readers interested ).
Important note: Not all of the concepts or plots listed here are total clichés themselves ! While most are, many are just good ideas (e. g. a surviving independent British space/aviation industry), marred by the same old unresearched assumptions of AH authors. Others are tolerable (e. g. alternate Israels, the greater proliferation or survival of airships/battleships than in our history, etc.), but can easily be written badly or be overdone to the point of irrelevance… Or worse - making the reader bored.