The PHP programming language can also be mixed with other programming languages, which is made possible by the use of 'underscoding'. PHP is used to power most of the dynamic visual features of a website, starting from the HTML codes to the various image libraries such as the JPEG or GIF image files. The major characteristics of PHP are its high level of standardisation, relative simplicity and robustness when compared to other common web development languages. The PHP source code implementation has been taken over by The PHP group now. It was first developed by Danish-American developer Rasmus Lerdorf in 1994 with the aim of using it as a programming language for the web. PHP is an all-in-one general-purpose programming language aimed at web development.