This thesis is intented to give the main ideas about Web Standards and it will give answers of some important core questions such as what is it Web Standards, why do we need to use them, and if it is used which kind of advantage programmers and end users will take of? Apart from that the main features of the latest version of HTML, HTML5 is important part of the thesis. Therefore, not only HTML5, as well as other new technology logics will be discussed. Building web applications with HTML5 features extends functionalities of the web pages, and gives big opportunity in order to use some new functionalities which is not possible to do with previous HTML versions. Beside of new functionalities, the thesis consists of some new security measurement of HTML5, such as using media content without any plug-in.