Why use DAML?

In real life when somebody is told something, he may be able tell something new by combining his new and old knowledge. Similar can be the case with computers when you tell something in XML to a computer, it may tell you something new in response, but it happens because of some other software that is not part of the XML specification. The implementation of that software can be of different type in different systems which will result in different answers from those systems. If you tell a computer something new in DAML, it can give you new information, based entirely on the DAML standard itself. Any system which conforms to DAML must have certain set of conclusions. The main use of DAML is that it gives computers an extra small degree of autonomy which can help it to do more useful work for people.

The difference between XML and DAML lies in the fact that a set of XML statements don’t let you conclude another XML statement whereas a set of DAML statements allow you to conclude another DAML statement. In DAML knowledge is explicitly stated but in XML to generate new data, we need to embed knowledge in some procedural code somewhere.

Take for example the following statement, "Parenthood is a more general relationship than motherhood." and "Lena is the mother of Steve" together allow a system conforming to DAML to conclude that "Lena is a parent of Steve". In this way, if a user poses a query to a DAML search system such as "Who are Steve's parents?", the system can respond that Lena is one of Steve's parents, even though that fact is not stated anywhere, but can only be derived by a DAML application.

More formally stated, give the statements

(motherOf subProperty parentOf)
(Lena motherOf Steve)

when stated in DAML, allows you to conclude

(Lena parentOf Steve)

based on the logical definition of "subProperty" as given in the DAML spec. The same information stated in XML does not allow you to assert the third fact. XML itself provides no semantics for its tags. One might create a program that assigns similar semantics to a "subProperty" tag, but since that semantics isn't part of the XML spec, applications could be written which conform to the XML spec, and yet do not make that assertion.

The example given above can be supported by other web languages like RDFS which are a step ahead of XML. DAML offers a host of standard properties like equivalence or some particular unique properties.

One can easily make out that there is similar utility in just about every domain: in finance where one might query about all bank accounts associated with a particular person (whether they are directly owned by, or held in trust for etc), in logistics where one wants to ask the rates for shipping to any eastern European city (where no such category has been predefined and only the countries in eastern Europe are listed). In DAML we have a kind of knowledge that can be dynamically applied to find an answer, rather than predefined procedures.

DAML provides the machines with the basic infrastructure which helps them to make inferences like human beings. DAML is just a start, but it’s a critical foundation for a web of information that machines can draw upon.