4. A filter engine system comprising: a processor coupled to a memory, the memory configured with instructions for implementing; an optimized filter sub-engine configured to accept an input that conforms to a language and process the input against a filter table associated with the optimized filter sub-engine, wherein the optimized filter sub-engine is configured to process only a subset of terms of the language, wherein the subset of terms of the language does not include all terms of the language, and wherein the language comprises a query language based on eXtensible Markup Language (XML), wherein the query language is XPath; a general filter sub-engine configured to accept the input and process the input against a filter table associated with the general filter sub-engine, wherein the general filter sub-engine is configured to process all terms of the input language; and an analyzer configured to determine whether the input can be processed by the optimized filter sub-engine and, if so, direct the input to the optimized filter sub-engine for processing, or if not, direct the input to the general filter sub-engine for processing.
4. A filter engine system comprising: a processor coupled to a memory, the memory configured with instructions for implementing; an optimized filter sub-engine configured to accept an input that conforms to a language and process the input against a filter table associated with the optimized filter sub-engine, wherein the optimized filter sub-engine is configured to process only a subset of terms of the language, wherein the subset of terms of the language does not include all terms of the language, and wherein the language comprises a query language based on eXtensible Markup Language (XML), wherein the query language is XPath; a general filter sub-engine configured to accept the input and process the input against a filter table associated with the general filter sub-engine, wherein the general filter sub-engine is configured to process all terms of the input language; and an analyzer configured to determine whether the input can be processed by the optimized filter sub-engine and, if so, direct the input to the optimized filter sub-engine for processing, or if not, direct the input to the general filter sub-engine for processing. 8. The filter engine system as recited in claim 4 , further comprising a sub-expression module that is configured to perform acts comprising: determine whether the input consists of different sub-expressions; in an event the input consists of different sub-expressions, directing each of the different sub-expressions contained in the input to the analyzer, wherein the analyzer is further configured to determine whether each of the different sub-expressions can be processed by the optimized filter sub-engine and to direct each of the different sub-expressions to an appropriate filter sub-engine for processing.