in certain styles, pinan shodan and pinan nidan are inverted - what certain styles call pinan shodan is what others call heian nidan, and vice versa. for example, the kata shotokan calls heian shodan, other styles, such as shitō-ryū call pinan nidan. another point to note is that shūkōkai teaches pinan nidan first, and pinan shodan second, believing pinan nidan to be the easier, more beginner-friendly kata. the order that is learnt in wado-ryu goes as follows,