The DIKW hierarchy - Data, Information, Knowledge, Wisdom
The DIKW hierarchy is a rough model for relating data, information, knowledge, and wisdom. Granted, the model lacks scientific precision and may not have a lot of functional utility, among numerous criticisms, but I personally find that it helps to clarify what level of refinement and robustness we are dealing with.
There is implicitly a lower-level below the DIKW hierarchy, the signal level where we have raw sensor readings before they are formatted into data.
Data (or a data item) has little meaning directly attached to it. We have primitive data types such as integers, floating point numbers, character strings, boolean flags, etc., and we have streams of data. We speak of data values or the value of a data item.
Information takes data and applies structure and rudimentary meaning. We have records, structures, database tables, and other methods and mechanisms for organizing raw data items into somewhat abstract structures. These structures may be coupled with methods for manipulating the information and rules that constrain the information and structures or define relationships among subsets of the information. This is the meat and potatoes of computation as we know it today.
Knowledge moves towards representation of meaning that may begin to approximate human knowledge. Knowledge has a meaning structure but may or may not be based on information structures as well. We may also approximate knowledge using semi-structured information.
Wisdom corresponds to judgment in the application of knowledge, but is not yet readily achievable in a typical computational environment.
This DIKW model is surely very limited and may not ultimately give us a lot of intellectual leverage, but it is a decent starting point.
I see the current Semantic Web as mostly focused at the information level, trying to give us computational power at the Web level that we currently have within individual computers and individual applications.
The hope is that once we have mastered information at the Web level, maybe then we can layer knowledge on top of that. And then maybe wisdom can be laid on top of that. Or so the fantasy goes.