The present invention provides an information processing device for estimating usage of contents and properly limiting functions realized through use of the contents in accordance with the estimation. Usage of contents is estimated by determining in which of cache memory means and content storage means the contents are stored. When the contents are processed or executed, it is determined whether to limit functions realized through processing or execution of the contents, on the basis of the estimated usage of the contents and function limit information showing a rule regarding limits on functions realized through processing or execution. On the basis of the determination, the functions realized through processing or execution of the contents are limited.