Natural Language Processing (NLP) aims to acquire, understand and generate the human languages such as English, French, Tamil, Hindi, etc.
SYMBOLIC APPROACHES TO NATURAL LANGUAGE PROCESSING
Symbolic Approaches also known as Rationalist approaches believe that significant part of the knowledge in the human mind is not derived by the senses but is fixed in advance, presumably by genetic inheritance. Noam Chomsky was the strong advocate of this approach. It was believed that machine can be made to function like human brain by giving some basic knowledge and reasoning mechanisms Linguistic knowledge is explicitly encoded in rule or other forms of representation. This helps automatic process of natural languages.
NATURAL LANGUAGE ANALYSIS
It runs into many stages, namely tokenization, lexical analysis, syntactic analysis, semantic analysis, and pragmatic analysis.
Syntactic analysis provides an order and structure of each sentence in the text. Semantic analysis is to find the literal meaning, and pragmatic analysis is to determine the meaning of the text in context. These major tasks are further broken down into, parsing and so on.
NATURAL LANGUAGE GENERATION
This is to generate fluent and coherent multi-sentential texts from an underlying source of information. The kind of text generated ranging from a single word or a phrase as an answer to a question to full-page explanations and even to the extent of speech depending upon the context.
EMPIRICAL APPROACHES TO NATURAL LANGUAGE PROCESSING
Empirical Approaches focus on the use of large amounts of data and the procedures involving statistical manipulations. Corpus, bulk of data in a particular format, comes handy for analysis. Crucial tasks using these approaches are POS tagging, alignment, collacations, word-sense-disambiguation, etc.
CHALLENGES IN NATURAL LANGUAGE PROCESSING
Still a perfect natural language processing system is developed. There are many problems like flexibility in the structure of sentences, ambiguity, etc.
Natural language processing applications require the availability of Lexical Resources, Corpora and Computational Models.