An information processing apparatus comprising: storage means for storing application data in a plurality of different states, wherein each of said different stored states of said application data is distinguished by time information indicating time at which said application data are created or changed; an application program for using said application data, said application program comprising: transmit means for transmitting time information to another application program; receive means for receiving time information from said another application program; time setting means for setting a desired time for said application program; control means for locating application data from said stored application data based on the desired time set by said time setting means, and for reproducing the state of said application program by using said located application data; wherein said time setting means is adapted to set said desired time for said application program based on said time information received from said another application program; and said control means is adapted to locate application data from said stored application data at a time closest to said desired time and to reproduce the state of said application program by using said located application data. storage means for storing application data in a plurality of different states, wherein each of said different stored states of said application data is distinguished by time information indicating time at which said application data are created or changed; an application program for using said application data, said application program comprising: transmit means for transmitting time information to another application program; receive means for receiving time information from said another application program; time setting means for setting a desired time for said application program; control means for locating application data from said stored application data based on the desired time set by said time setting means, and for reproducing the state of said application program by using said located application data; wherein said time setting means is adapted to set said desired time for said application program based on said time information received from said another application program; and said control means is adapted to locate application data from said stored application data at a time closest to said desired time and to reproduce the state of said application program by using said located application data. transmit means for transmitting time information to another application program; receive means for receiving time information from said another application program; time setting means for setting a desired time for said application program; control means for locating application data from said stored application data based on the desired time set by said time setting means, and for reproducing the state of said application program by using said located application data; wherein said time setting means is adapted to set said desired time for said application program based on said time information received from said another application program; and said control means is adapted to locate application data from said stored application data at a time closest to said desired time and to reproduce the state of said application program by using said located application data.