PostgreSQL is an advanced relational database management system, which can be used on a number of platforms (UNIX, Linux, FreeBSD, OpenSolaris, Windows) and with many scripting languages (Perl, PHP, Python, Java, Ruby). Since it is open-source, it can be freely modified to suit the requirements of any developer who employs it. PostgreSQL is also among the most reliable and secure database systems, with superior performance in managing sophisticated operations when compared with similar systems. It is ideal for large-scale applications since a single PostgreSQL database doesn't have a limit for the size, while an individual table may be up to 32 Gigabytes. It's not a surprise that a number of business, educational and governmental entities are already using PostgreSQL - Skype, the University of California, Berkeley and the US Department of Labor being only a couple of examples.