  The paper presents an extension of Shannon fuzzy entropy for intuitionistic
fuzzy one. Firstly, we presented a new formula for calculating the distance and
similarity of intuitionistic fuzzy information. Then, we constructed measures
for information features like score, certainty and uncertainty. Also, a new
concept was introduced, namely escort fuzzy information. Then, using the escort
fuzzy information, Shannon's formula for intuitionistic fuzzy information was
obtained. It should be underlined that Shannon's entropy for intuitionistic
fuzzy information verifies the four defining conditions of intuitionistic fuzzy
uncertainty. The measures of its two components were also identified: fuzziness
(ambiguity) and incompleteness (ignorance).
