How does numbering of adventures work?

[Kyle Ropp]

Against the slave lords was a1-4 right? what makes it A vs B or C and i just assume the number that comes after that is just the placement in the series.
also was against the slave lords a1 for Next or do these markings carry across from other editions?

bonus points for telling me what was the first a1 or what the first published adventure was

 

[M.L. Martin]

It's a two-part code of letters and numbers. Letter designates the series; number designates the order of publication within the series.

For AD&D as of 1990, according to Lawrence Schick's Heroic Worlds:

• A=Aerie of the Slave Lords series
• C=Competition series (tournament modules) (This is why D&D Champion-level are designated CM.)
• CA=City Adventure series (Lankhmar)
• CB=Conan the Barbarian
• D=Drow
• DL=Dragonlance series (the original modules)
• DLA=Dragonlance Adventure series
• DLC=Dragonlance Classics series (reprints of the original modules)
• DLE=Dragonlance Epic series
• DLR=Dragonlance Reference series (sourcebooks)
• DMGR=Dungeon Master's Guide Reference
• DQ=DragonQuest crossover adventures (the old 1980s SPI game)
• EX=Expansion series (extensions of existing dungeons)
• FR=Forgotten Realms
• FRA=Forgotten Realms Adventure series
• FRC=Forgotten Realms Companion series (computer game tie-ins)
• FRE=Forgotten Realms Epic series
• FROA=Forgotten Realms Oriental Adventures
• G=Giants
• GDQ=Giants/Drow/Queen of the Demonweb Pits compilation
• GM=Game Master (from a scenario magazine)
• H=High (level)
• I=Intermediate (level)
• L=Lendore Isles
• LC=Living City
• LNA=Lankhmar/Nehwon
• MV=Magic Viewer (using those red plastic filters, IIRC)
• N=Novice (players/characters)
• OA=Oriental Adventures
• OP=Outer Planes
• PHBR=Player's Handbook Reference series
• Q=Queen of the Demonweb Pits
• R=RPGA
• REF=Reference (DM's supplements)
• RPGA=Self-explanatory
• RS=Red Sonja (also used by accident for Ravenloft Sourcebook once)
• S=Special series (stand-alone scenarios, usually tournaments)
• SJA=Spelljammer Adventures
• SJR=Spelljammer Reference
• T=Temple of Elemental Evil
• U=Underwater
• UK=United Kingdom-designed adventures
• WG=World of Greyhawk
• WGA=World of Greyhawk Adventures
• WGR=World of Greyhawk Reference

Some subsequent series were added to these until TSR abandoned the nomenclature in 1994. HR=Historical Reference is the most famous; most of the others are setting-specific, usually an abbreviation of the setting (R=Ravenloft, DS=Dark Sun, ALQ=Al-Qadim) followed by a one-letter code for the type of product (R=Reference or S=Sourcebook for source material, A=Adventure, M=Module or Q=Quest for adventures) and then the numeric code to identify the specific item.