Excluded
- SE sites with non-English interface (localized Stack Overflow sites and Russian language in Russian)
- Meta Stack Exchange
- Per-site metas, including Area 51 Discussions
- Stack Apps
Limited (by hotness score)
These sites can still contribute the same number of questions to Hot Network Questions, but their questions need higher hotness score to be selected.
Heavily
Quite
- Programmers / Software Engineering
- The Workplace
References: How is hotness score calculated at larger sites?, penalty factor per-site (higher value = smaller hotness score)
Limited (by number of questions)
These sites' questions can still end up in Hot Network Questions with the same hotness score, but are limited to contributing fewer than the default five per site.
- Interpersonal Skills - 1 question at a time
Past occurrences
- Christianity (quite penalized; effectively excluded)
- Sexuality (excluded)
- Interpersonal Skills (excluded)
