Takes a text string as input, splits the text into sentences, and parses each sentence, outputting the flattened parse tree into an object list. The parse tree is a decomposition of the sentence according to its grammatical structure, splitting out phrases, determining the subject or object of a verb, etc. The parser here is probabilistic and will output what it determines to be the most likely parse of a given sentence. You can read more about how it works http://nlp.stanford.edu/software/lex-parser.shtml.
Parts are tagged according to the conventions of the Penn Treebank Project (http://www.cis.upenn.edu/~treebank/). For example, a plural noun is denoted NNS, a singular or mass noun is NN, and a determiner (such as a/an, every, no, the,another, any, some, each, etc.) as DT.
For more information, please refer to http://nlp.stanford.edu/software/corenlp.shtml or Manning, Christopher D., Surdeanu, Mihai, Bauer, John, Finkel, Jenny, Bethard, Steven J., and McClosky, David. 2014. The Stanford CoreNLP Natural Language Processing Toolkit. In Proceedings of 52nd Annual Meeting of the Association for Computational Linguistics: System Demonstrations, pp. 55-60.