Collection home directory-The directory in which collection data is stored. Collection data includes indexes and pointers to a set of documents. Source documents are not copied to the collection directory.
Partition directory (parts)-The directory in which collection partition data is stored. A partition is an internal structure used to store the word index and documents table data for a collection.
Style directory (style)-The directory in which the collection style files are stored. The style files contain configuration settings which are used by the engine to index and view documents. Once the collection is created, all style information is read from this directory, not the original source directory.
Topic index directory (topcidx)-When topics are defined and then indexed against the collection, the resulting topic set index is stored in this directory. The topic set index is an optional component of a collection.