9. A system to perform a semantic search to retrieve documents from a document repository, comprising: a memory configured to store and retrieve data, including instructions; a processor configured to execute instructions retrieved from the memory to perform the steps: accepting a search phrase; analyzing the search phrase and suggesting a plurality of semantic search phrases generated from a stored vocabulary of an ontology to suggest a context; accepting a first semantic search phrase selected from the plurality of semantic search phrases; storing in a storage medium at least one unstructured document; indexing and semantically tagging a plurality of documents including the at least one unstructured document in the storage medium, wherein indexing and semantically tagging the plurality of documents comprises weighing a plurality of semantic concepts generated from a plurality of extracted noun phrases, wherein the plurality of semantic concepts is weighed by term significance (TS) scores, wherein the TS scores are calculated with both semantic and statistical information, and wherein the semantic information includes lexical chaining Word Sense Disambiguation (WSD) scores and Depth and Information Content (IC) values, and the statistical information includes Term Frequency (TF) and Inverse Google Popularity (IGP); extracting a plurality of semantic tags from the indexed and semantically tagged documents; and defining one or more groups based on the indexed and semantically tagged documents, wherein the documents in the plurality of documents are indexed with unique identifications of semantic tags, and wherein the processor searches the indexed documents based on a unique identification of the first semantic search phrase.
9. A system to perform a semantic search to retrieve documents from a document repository, comprising: a memory configured to store and retrieve data, including instructions; a processor configured to execute instructions retrieved from the memory to perform the steps: accepting a search phrase; analyzing the search phrase and suggesting a plurality of semantic search phrases generated from a stored vocabulary of an ontology to suggest a context; accepting a first semantic search phrase selected from the plurality of semantic search phrases; storing in a storage medium at least one unstructured document; indexing and semantically tagging a plurality of documents including the at least one unstructured document in the storage medium, wherein indexing and semantically tagging the plurality of documents comprises weighing a plurality of semantic concepts generated from a plurality of extracted noun phrases, wherein the plurality of semantic concepts is weighed by term significance (TS) scores, wherein the TS scores are calculated with both semantic and statistical information, and wherein the semantic information includes lexical chaining Word Sense Disambiguation (WSD) scores and Depth and Information Content (IC) values, and the statistical information includes Term Frequency (TF) and Inverse Google Popularity (IGP); extracting a plurality of semantic tags from the indexed and semantically tagged documents; and defining one or more groups based on the indexed and semantically tagged documents, wherein the documents in the plurality of documents are indexed with unique identifications of semantic tags, and wherein the processor searches the indexed documents based on a unique identification of the first semantic search phrase. 13. The system of claim 9 , wherein at least one group of the plurality of groups is determined by a keyword that occurs in a selected document in the storage medium.