What are CSS3 modules?

Question

I can not understand the concept of modules. What are these modules and how do they differ from CSS2? Can someone explain these modules in a simple way? And why do these modules make CSS3 different from CSS2?

Answer 1

CSS Level 2 is a monolithic specification. You have one sectioned specification, with each section describing the basic component of the CSS formatting model, for example:

• Selectors
• Cascading and inheritance
• Window model
• Colors and Background
• Fonts

The defining CSS 2 level standard is CSS2.1 or CSS 2 Level 1, which became a recommendation in 2011 after a set of changes to the 1998 standard to improve interoperability. The CSS2.1 specification can be found here (with the examples above related to individual sections).

Post-CSS2 you have modules, which are basically different sections of CSS2, divided into their own specifications. The above examples from CSS2 have the following corresponding modules:

• Selectors
• Cascading and inheritance
• Window model
• Colors and backgrounds (yes, this one section is divided into two modules)
• Fonts

This means that you have several specifications that all relate to CSS, each with its own independent development path. This means that different modules can move towards implementation and standardization at different speeds, without having to depend on the rest of CSS as a language (which was the main reason that CSS2.1 has become a recommendation for so long after standardizing CSS2). These specifications are collectively referred to as CSS3, or "CSS level 3," although each of them goes through the levels on its own, making it somewhat wrong.

CSS3 and its modulation system are described in more detail in this other answer .

Answer 2

CSS Level 2 is a "specification"

CSS Level 3 is a “spec sheet”. Each specification (module) defines (basically) an autonomous set of related functions, such as borders and backgrounds .

This allows the various specifications to advance to the recommendations without having to wait for the rest.

Answer 3

What is the difference between css2 and css3? a good answer is given at http://webdesign.about.com/od/css3/a/differences-css2-css3.htm CSS3 has been divided into different sections called modules. Each of these modules does this through the W3C at different stages of the recommendation process. Hope this helps.