Chat rooms and forums

Forums for general APL discussion include:
 * The APL Orchard on Stack Exchange
 * #aplfarm:matrix.org and the +aplfarm:matrix.org collection of channels
 * #apl IRC room on Freenode
 * r/apljk on Reddit
 * comp.lang.apl newsgroup (see also APL On The Internet)
 * APL Dinosaurs group on Facebook

Additionally, several APL dialects have dedicated online forums:
 * APL+Win: APLDN (APL2000 Developer Network Forum)
 * APLX: Support forum for APLX
 * Dyalog APL: Dyalog Forums
 * NARS2000: NARS2000 Forum