Here are the top 100 tags on IFDB, listed loosely and imperfectly in categories. I was trying to see what kinds of categories were represented among the top tags. (Maybe I should have started a separate thread?)
Genres
adaptation (130)
Adventure (157)
comedy (187)
fantasy (866)
historical (157)
horror (776)
humor (473)
Mystery (418)
romance (286)
rpg (470)
science fiction (685)
slice of life (183)
Surreal (305)
visual novel (136)
Authoring systems
adrift (485)
Adrift 4 (303)
adventuron (160)
ChoiceScript (182)
ChooseYourStory (232)
Inform (174)
Inform 6 (135)
inform 7 (313)
TADS (491)
tads 2 (366)
twine (1338)
Eamon (280)
Competitions
Ectocomp game (410)
IF Short Games Showcase (163)
IFComp Game (1418)
IntroComp (173)
La Petite Mort (164)
Le Grand Guignol (161)
Mini-comp (186)
neo-twiny jam (256)
Neo-Twiny Jam 2024 (137)
Spring Thing Game (296)
speed IF (139)
speedif (330)
Protagonists
child protagonist (186)
female protagonist (748)
gender-neutral protagonist (454)
male protagonist (583)
multiple protagonists (205)
nonhuman protagonist (408)
teenage protagonist (167)
Content/subject matter
dragon (160)
LGBTQ+ (255)
magic (251)
profanity (245)
sexual content (283)
space (148)
violence (459)
Xyzzy response (535)
Parser/choice/interface
CYOA (797)
choice-based (766)
hypertext (436)
parser (1764)
primitive parser (128)
two-word parser (715)
Prose characteristics
first person (345)
present tense (188)
second person (341)
third person (175)
word count limit (313)
Technical features
bookmarks (197)
built-in hints (351)
gender choice (188)
landscape mode (196)
score (231)
undo (152)
External Resources
ClubFloyd transcript (680)
I6 source available (224)
I7 source available (197)
source available (753)
walkthrough (1877)
Types of Gameplay
combat (144)
conversation (132)
maze (195)
puzzleless (198)
Multimedia
cover art (1689)
graphics (1131)
music (342)
sound (621)
Language
foreign language (268)
French (170)
german (216)
Spanish (173)
Platform
C64 (181)
desktop (131)
zx spectrum (145)
Author information
collaboration (148)
first effort (194)
Award/Prize
Colossal cash prize (173)
Winner of a comp (313)
Game/Story Structure
linear (151)
multiple endings (702)
Setting
single room (253)
Length
short (810)
License
commercial (505)
Publisher
choice of games (165)