All eight classes at a glance

The indeclinable noun: definition, rule and eight classes

1. Pronouns — هُوَ
2. Demonstratives — هَذَا
3. Relatives — الَّذِي
4. Verb-names — صَهْ
5. Sound-names — غَاقِ
6. Certain compounds — أَحَدَ عَشَرَ
7. Kināyāt — كَمْ
8. Certain adverbs — حَيْثُ

These are recognition examples, not an assertion that each category has no declinable exceptions.