ASP (Active Server Pages) is a standard developed by Microsoft in 1996 for the development of interactive web applications (page with dynamic content). The content of an ASP webpage (with the .asp extension) may differ depending on certain parameters (information stored in a database, the user preferences, ...) while a classic webpage (with the .htm or .html extension) will display the same information continuously.
ASP can be integrated in a web page in HTML using special tags that will instruct the Web server that the code included within these tags must be interpreted and data (usually HTML code) must be returned to the client browser.
Thus, Active Server Pages is part of a 3-tier architecture. This term means that a server that supports Active Server Pages can be used as an intermediary between the client browser and a database, using the ADO (ActiveX Data Objects) technology, which provides the elements necessary to initiate connection to a databases management system and the handling of data using the SQL language.
Characteristics of Active Server Pages
ASP were designed to operate on the Microsoft Web server called Microsoft IIS (Internet Information Server). This web server, developed by Microsoft in 1996, has the advantage of being free, it runs under the Microsoft Windows NT operating system .
However, this proprietary technology is now available on other web servers, like the Netscape FastTrack Server for Chili!Software and other servers including Apache (with the Apache::ASP module), making it possible to create websites using ASP technology on various platforms (Unix, Linux, PowerPC, ...).
The basic objects of Active Server Pages
Active Server Pages are made up of the objects that will be "processed" by the server. The seven basic objects are:
Application: it is the object representing the web application itself, that is to say, an object containing all information shared by visitors connected to the online application.
ObjectContext: it can control any transactions with the Microsoft Transaction Server (MTS: Microsoft Transaction Server).
Request: This object is used to retrieve information sent to the server in the HTTP request from the client.
Response: It is used to create and send the HTTP response to the client (browser).
Server: it contains information specific to the web server.
Session: it allows you to manage user sessions, that is to say to keep information from one page to another.
ASPError: this object retrieves and sets the errors encountered during the execution of ASP scripts.