Decimal (Ukrainian) I (as opposed to octal I): In the early Cyrillic alphabet there was little or no distinction between the letters и (izhe) and і (i), descended from the Greek letters η (eta) and ι (iota). They both remained in the alphabetical repertoire because they represented different numbers in the Cyrillic numeral system, eight and ten, and are therefore sometimes referred to as octal I and decimal I.
алсо: http://en.wikipedia.org/wiki/Palochka
алсо: http://en.wikipedia.org/wiki/Palochka