A content management system (abbreviated CMS, German " Content Management System") is a software to collaboratively design, editing and organization of content (Content ) mostly in web pages, but also in other forms of media. These may consist of text and multimedia documents. An author with access privileges such a system can in many cases operate with little programming or HTML knowledge, as the majority of the systems have a graphical user interface.
Special emphasis is placed at CMS on a media- neutral data management. So may be available, for example as a PDF or HTML document contents on request; the formats are generated with fully dynamic systems only when the query from the database.
Joomla, Drupal, TYPO3 and WordPress are amongst the most popular open source CMS. WordPress and Joomla are currently the most widely used. From numerous authorities of the German federal government (eg Federal Administrative Office, Federal Office for Consumer Protection and Food Safety, ministries ) of Government Site Builder ( GSB) is used for the care of their online appearances.
- 4.1 Dynamics and Statics 4.1.1 Fully dynamic systems
- 4.1.2 Static Systems
- 4.1.3 Hybrid Systems
- 4.1.4 Semi-static systems
Although technically accurate would have to be spoken by the web content management system WCMS or, the more global term CMS is used in common parlance for systems or modules, the sole purpose of creating sites. Desktop CMS do this on a local machine with subsequent uploading, other systems directly on a Web server delivering.
Add delimitation of systems with offline content used is called in the above systems by WCMS. In order for the difference to those systems is approximately clarified in the publishing industry, serving also other output media in addition to the Web, such as print or radio. Web content management can be seen as a component in the Enterprise Content Management.
The main purpose of a CMS is to manage and target groups, as well as barrier-free representation of text or multimedia content for the web browser.
In addition to the main content of a page other content be integrated, such as
- Meta-information such as publication date, author, table of contents,
- Multiple use of content by transclusions and
- External data sources, such as calendars, cards and user data (eg Gravatar ) via third party application programming interfaces ( API) or web services such as RSS.
Addition to the presentation of content, the CMS automatically offers alternative content aggregation:
- Groups to categories
- Temporal change and re- created content,
- Machine-readable output of content for feeds (such as Atom, RSS ), micro formats or programming interfaces for integration with other services (eg as JSON )
- Similar, possibly for the reader interesting, content and
- Print version.
Through the built-in content lifecycle management content can be automatically published or archived time-limited.
Integrated search engines also allow the user to browse the contents of a Web page. These search engines are either already integrated in the software or can be integrated as external services. OpenSearch allows access to the search function from outside the website. Do not confuse these options with those of so-called meta-search engines.
Creating and editing content is usually about an online word processing module (so-called inline editing or In Place Editing) or files directly on the web host; older systems still offer to separate client software for editing.
In the online word processor, either a separate backend is offered or guardians may edit them directly in the presentation. The text is entered, depending on the level of knowledge of the editor or the extent of the content management system, either through a WYSIWYG or a text editor. This content can be stored in a simplified markup language (for example, Markdown ) or pure HTML. To view the content in its final version, a preview function is usually offered.
With an integrated version control the build process will be archived at the same time and recorded. Certain versions can be restored in case of failure.
To prevent unauthorized changes and to be able to trace changes, processing plant must authenticate users and roles are assigned on the basis of an authorization concept. Users are usually distinguished hierarchically, such as certain editors can create articles, but must be enabled by administrators. A vertical roller system then allows certain user groups only in certain areas to work (eg department).
These roles and rights structure can represent simple Releases by four-eyes principle or complex workflows. Several people be able to participate in such workflows with different tasks, such as authors, editors and webmasters, produce, approve, or unlock the content. This is called content management systems.
Above all, social media websites, such as blogs, are characterized by a high possibility of substantive involvement of the reader. Users can leave on specific content or set external Trackbacks entries in guest books, comments. With user-generated content to user interaction and content creation mix.
In addition to the usability features to user interaction must be efficient against spamdexing especially. This is achieved mainly with CAPTCHAs, nofollow and DNS -based Blackhole List.
In collaboration with the CMS Web server can partially take over tasks of transmission and URL structure. Especially domain forwarders, Clean URLs and permalinks are configured in the CMS. Also, error pages (404 ) can be delivered by a CMS.
Through multi-tenancy multiple independent websites may be operated.
To expand CMS as individually as possible, are usually offered plug-ins.
If more complex functions mapped one speaks of a Web application.
The actual content is often stored in databases, as these allow faster access and make Datenbankindizies for categories, lists and feeds. Smaller CMS can also save text files contents but. The database is supported by virtually all CMS MySQL, but often find PostgreSQL or Microsoft SQL Server using.
Content management systems link the stored contents with styles and pass it to the delivering server. Software architectural usually comes the Model View Controller design pattern for use.
Given the close relationship and dependence between these software elements, these are usually installed together. For Open Source CMS there are the bundles LAMP and XAMPP for development environments. Physically running CMS on hosts, but which are offered by hosting providers as Web hosting or application service.
Especially Open Source CMS try not natively offer all possible or desired features, but (eg jQuery) to allow through server-side and client-side hooks standard libraries to integrate plug-ins.
Dynamics and statics
CM systems differ in the type of delivery of the created pages to the user:
Fully dynamic systems
Fully dynamic systems produce requested documents each time you call new dynamic, that is, templates, and content are interpreted only when called up or merged and output. Advantages: The site is always "current"; personalization for the surfer is usually very simple or even already exists. Cons: The recalculation at each side delivery may under high load (for instance, a high number of visitors ) to a delayed delivery of the site or of defective equipment / configuration for computing capacity in proportion to the number of simultaneously serviced user to server overload and in extreme cases, system failure. A measure to reduce the load is caching.
Static systems generate the individual web pages from templates and content as a statically stored in the file system or possibly in a database. The end product thus obtained documents that require no interpretation on the part of a server technology such as ASP, JSP or PHP more and thus can be directly issued by the web server, which is reflected in the output speed. This has the advantage that even simple web hosting product may be sufficient as a base. Disadvantage can be that may turn out to application requirements grow by greater complexity in conjunction with the desire for very short update cycles, such a system to be unsuitable.
Pure static systems form the historical origin of the CMS and however - rarely used - in this original form.
Hybrid systems combine the advantages of static and fully dynamic page generation. Only the content that must be generated dynamically from a database ( eg news, search queries, personalized content or store data) are read at runtime from the database. Any other content that is not constantly subjected to changes (such as the page structure, navigation, as well as certain texts and images) are static.
Semi-static systems generate the content so that it is static, but also dynamic at the same time, that is, there are all data stored directly in statically generated files, which are then output when called immediately. The dynamic content is generated if a code in the programming language in which it will be included or changed individual records or newly created.