A 
system and method capable of reading 
machine-readable labels from physical objects, reading coordinate labels of geographical locations, reading 
timestamp labels from an internal 
clock, accepting 
digital text string labels as input obtained directly from a keyboard type 
input device, or indirectly using a speech-to-text engine transforming any other 
label type information encoding into 
digital data by some transduction means, and treating these different labels uniformly as object identifiers for performing various indexing operations such as content authoring, playback, 
annotation and feedback. The 
system further allows for the aggregating of object identifiers and their associated content into a single addressable unit called a tour. The 
system can function in an authoring and a playback mode. The authoring mode permits new audio / text / 
graphics / video messages to be recorded and bound to an 
object identifier. The playback mode triggers playback of the recorded messages when the 
object identifier accessed. In the authoring mode, the system supports content authoring that can be done coincident with 
object identifier creation thereby enabling authored content to be unambiguously bound to the object identifier. In the playback mode, the system can be programmed to accept / solicit annotations / feedback from a user which may also be recorded and unambiguously bound to the object identifier.