Overview – What is PST File Extension?
PST stands for the Personal storage table is the default self-contained, stand alone, the structured binary file format used by the Microsoft Outlook. Personal storage table (pst) file is designed in order to keep the entire data at one place. This data includes emails, calenders, notes, contacts, tasks etc.
It uses fixed block based methodology for allocating memory. The file is enlarged by pre-defined sum of bytes and files preserves or save the information internally regarding the allocated and non-allocated blocks. So when email messages are added to PST file, the PST file size is adjusted accordingly by the Outlook application. When any messages are removed or deleted, file size remains unchanged marking space unallocated where future items will be saved. Thus it has become easier to recover deleted data from PST files.
The PST file created automatically when user creates Outlook profile on desktop either using the POP3 or IMAP configuration. The data in the PST file stored in compressed or encrypted form depends on the settings that you have made in Outlook Application.
TYPES OF PST FILE:-
ANSI » it is bequest format that has 2gb storage space limitation. It work only on the below versions of outlook 2002
UNICODE » The storage capacity of this pst file is 20 GB in outlook 2007 and up-to 50 GB in outlook 2010 and 2013. it also known as the advance format of pst file extension.
The PST file architecture is designed or structured in three layers:-
NDB » NODE DATABASE LAYER
:-It includes the header information, file allocation information and the nodes and blocks that holds the message data and nodes that helps locate data. It has two nodes
node b treeblock b tree
LTP » (LIST, TABLE, PROPERTIES) :-It basically concerned with properties that its stores in two dimensional table.
MESSAGING LAYER :-It combines the above two layers into messages, attachments, properties and folders.
Microsoft Outlook is the Pesonal information Manager developed by the Microsoft Inc. To store the Outlook data such as emails, calendars, tasks, journal etc,. Microsoft Developed the PST file Format.