How to know what card to buy?

Hi! I would be travelling to Tokyo Kyoto and Osaka next week. How do i know whether to buy locca card, or pasmo or suica? Any advice? Thank you very much

The cards are regional so it depends on where you will go first. For example, if you land in Narita then you'll get a suica card. If you land at KIX then get an icoca card.

http://www.japan-guide.com/e/e2359_003.html

Thank you! Appreciate the reply!

If I understand the use of the cards, all cards work in every region? for example, a pasmo card also works in Tokyo and a suica card works in Kyoto, but every region only has a certain type for sale?

At one point in time, SUICA only worked in JR East area of influence, ICOCA in JR West, KITACA in JR Hokkaido, etc. but now they're interlaced ALMOST 100%. There are a few places where the ICOCA works and not the SUICA and so on, but very few.