Web technologies

These FAQs briefly summarise some of the web technologies utilised by Composr.

For more information, check out these tutorials:
Question What are cookies and how do they work?
Answer A cookie is a small piece of data that a website stores on a user's computer. It is sent from the user's web browser to the web server each time a page is viewed. Cookies are used for various purposes, including:
  • User identification: Cookies can be used to identify a specific user, even if they are not logged in. This allows websites to remember user preferences, shopping cart contents, and other information.
  • Tracking user behavior: Cookies can be used to track user behavior on a website, such as the pages they visit and the links they click. This information can be used to improve the website's design and content.
  • Advertising: Cookies can be used to deliver targeted advertising to users based on their browsing history.

There are two main types of cookies:
  • Session cookies: These cookies are temporary and are deleted when the user closes their web browser. They are often used to store information about the user's current session, such as the items in their shopping cart.
  • Persistent cookies: These cookies are stored on the user's computer for a longer period. They can be used to remember user preferences, such as their login details or language settings.
Question What is the difference between cookies and sessions?
Answer While both cookies and sessions are used for user identification and maintaining state, there are key differences:
  • Storage: Cookies are stored on the user's computer, while sessions are stored on the server.
  • Expiration: Session cookies expire when the browser is closed, while persistent cookies have a set expiration date. Sessions typically expire after a period of inactivity.
  • Data sensitivity: Sessions are generally used for more sensitive data, as the information is not stored on the user's computer and therefore less likely to be stolen by a hacker.

Composr uses both cookies and sessions. Session cookies are primarily used for user identification (such as anonymously matching a user to a session in the server database), while persistent cookies can be used for remembering login details if the user chooses.
Question How does JavaScript enhance website interactivity?
Answer JavaScript is a programming language that runs in web browsers, allowing for dynamic and interactive elements on web pages. It enables features like:
  • Dynamic content updates: Modifying page content without requiring a full page reload.
  • User interface enhancements: Creating interactive elements like dropdown menus, image sliders, and form validation.
  • Animations and visual effects: Adding visual appeal and engaging user experiences.
  • Asynchronous communication: Fetching data from, or sending data to, servers in the background without disrupting user interaction.

Composr relies on JavaScript for its default theme and administrative features.
Question Why is understanding XHTML important for website customization?
Answer XHTML (Extensible HyperText Markup Language) is the language used to structure web page content. It defines the various elements of a webpage, such as headings, paragraphs, images, and links.

Understanding XHTML is crucial for website customization because it allows you to:
  • Modify page layout: Change the arrangement and positioning of elements on a page.
  • Add new content: Insert additional text, images, or other multimedia elements.
  • Customize the appearance of existing elements: Change fonts, colors, sizes, and other visual styles.
  • Integrate interactive features: Embed JavaScript code for dynamic functionality.

Composr uses XHTML for its templates, allowing users to extensively customize the website's design and layout.
Question What is CSS and how does it impact website design?
Answer CSS (Cascading Style Sheets) is a language used to describe the visual presentation of a web page written in HTML or XHTML. It controls aspects like:
  • Fonts and typography: Defining font families, sizes, weights, and styles.
  • Colors and backgrounds: Setting colors for text, backgrounds, borders, and other elements.
  • Layout and positioning: Controlling the placement and arrangement of elements on a page.
  • Visual effects: Adding shadows, gradients, transitions, and other visual enhancements.

By separating content structure (XHTML) from visual presentation (CSS), websites become easier to maintain and update. Changes to the design can be made without altering the underlying HTML structure.

Composr utilizes CSS extensively for theming, allowing users to manipulate the website's visual appearance.
Question How does Composr handle browser compatibility?
Answer Composr aims to support all modern browsers, including the latest versions of Chrome, Firefox, Safari, Edge, and Internet Explorer 11. It is designed to work seamlessly with browsers that automatically update, like Chrome and Firefox. For browsers with manual updates, Composr generally supports the last two releases.

While not explicitly supported, Composr will often address bug reports for other popular browsers like Opera, Chromium, and Konqueror. Additionally, Composr strives to provide an accessible experience for text-mode browsers and those designed for users with disabilities.
Question What are the recommended desktop settings for viewing a Composr website?
Answer A minimum screen resolution of 1024x768 is strongly recommended for viewing a Composr website. This is the minimum resolution for which the default theme is designed. Using a lower resolution might lead to display issues or an unsatisfactory browsing experience. As of version 11, smaller resolutions will often trigger the mobile layout automatically (responsiveness) to ensure a better UI for smaller displays.
Question How can I test my website's compatibility across different browsers and devices?
Answer Testing your website on different browsers and devices can be challenging due to operating system limitations and device availability. Here are some solutions:
  • Virtual Machines: Use virtual machines to run different operating systems and test various Internet Explorer versions.
  • Device Emulation: Use built-in device emulation features in browsers like Chrome to simulate mobile devices.
  • Online Testing Services: Employ commercial online testing services like BrowserStack to access a wide range of browsers and devices hosted in the cloud.
  • Real Devices: Conduct testing on physical mobile devices for a more realistic user experience.
Question How does Composr ensure printed web pages look appropriate?
Answer Composr uses a combination of approaches to ensure printed web pages have a suitable layout:
  • Automatic browser behavior: Browsers typically disable background images when printing.
  • CSS print stylesheets: Composr utilizes CSS to define specific display rules for printed versions of pages, such as removing margins and hiding social media links.
  • wide_print parameter: This parameter, activated through specific links or specifying it in the URL, further influences page layout for printing.
Question What web technologies does Composr use beyond HTML, CSS, and JavaScript?
Answer Composr relies on a wide range of web technologies (depending on what features and settings you use), including:
  • Protocols: HTTP/HTTPS, FTP, SFTP, SMTP, IMAP, POP3, DNS, and others
  • Data formats: XML, JSON, CSV, PHP's serialized format, iCalendar, and various image and archive formats
  • Standards: Accessibility standards (WCAG, WAI-ARIA), metadata standards (Open Graph, schema.org, Dublin Core), and microformats
  • Server-side technologies: PHP, SQL (for database interaction)
  • Composr-specific technologies: Tempcode (template system), Comcode (content language), Page-links, Filtercode, Selectcode, and Language packs