- Do people (in different countries) use different list-style-type for numbering list element? (e.g. shopping list, to-do list, list of students in school, ...)
Yes in some countries using different alphabets to Latin
- If so, does Greek use greek, Japanese use katakana, Armenians armenian, ... all the time (in every situation) or maybe in a few cases ?
While not in EVERY case, depends on the place, you're mixing extremely different cultures and not giving many details about situations, so the answer is extremely broad
- Or maybe everyone just use decimal or very sometimes latin for everything?
Most people uses ARABIC NUMERALS (if we're going to talk properly) which is what in CSS we use as decimal
or decimal-leading-zero
values. However, they all have uses. As an example, in western cultures, the use of Roman numbers is widespread in literature, formal documentation and such.
Finally, localization has a more important meaning: accessibility. When you use aural style sheets, it's not the same for a visually impaired person to use this:
li{list-style-type: hiragana;}
or
li{list-style-type: decimal;}
it's a world of difference. Literally.
Also, keep in mind that you can use selectors for internationalization, so depending on what you want to do and your target, you might be interested in using language targeting, like
body:lang(jp)
for your Japanese users, and leave a regular English version for everyone else, so you'll obviously serve an appropriate version that includes listings and everything