As you can see when you start the Registry Editor, Registry has six main branches, or "root key" Every branch that used has different class of information.

HKEY_LOCAL_MACHINE is the branch that contains information specifically relating to the computer. The example includes hardware and software installed, driver for hardware and configuration data for software. The content of this branch is stored in SYSTEM.DAT file in the Windows Registry 9x.  

The data recorded in the Register belong into two different categories: information system and user information. Information system is only related to the computer itself. This includes information about hardware and its drivers and so on. It also may include information relating to the software that has been installed on the machine.

User information is all the settings related to computer user, including its personal preferences. A Windows 98 computer can only have one user, but Windows NT/2000 supports multiple users and affirm that you log on to the system to use it. Windows 9 xs/Me also permits the use of user profiles. Requirement that a user can access the personal settings when logged on is using a different computer on the network. To meet this, the system and user information are stored in separate files, and Registry will use different user information depending on the file name of the user or profile.

Each operating system and application needs a place to store its configuration settings and user preferences. Some of the settings required by the MS-DOS that stored in CONFIG.SYS file usual text file. DOS programs must make their own settings for storing the user’s settings.

Initially Windows uses INI files – which are text files that organized in a simple format and can be read and written with specific routines which are available for Windows programs. Windows has one configuration file, it is SYSTEM.INI, which is used for all internal settings and more, WIN.INI for user preference. The system works pretty well, and still used by some Windows programs, but it has some drawbacks. INI files are slow to access and limited in size of 64KB. There is also the only one INI file per program per computer, making it difficult to have different settings for each user's computer.

JavaScript is a scripting language made that popular on the internet. JavaScript can work on most popular browsers such as Internet Explorer (IE), Mozilla Firefox, Netscape, and Opera. JavaScript code can be pasted on a web page using a script tag.

JavaScript has a meaning as language with form of scripts collection that the function is to run on an HTML document. Throughout the history of the internet, this language is the first scripts language of for web. This language can be considered as a programming language to provide additional capability to the HTML language with allowing executing commands on the user, meaning that in the browser instead of on the side of the web server.