Collaboration is an important part of the Drupal community. The principle of collaboration applies equally to how people in the community engage with each other and to how modules are written.
I mentioned the Libraries API in a spearate post when I discussed creating a slideshow. The specific example was that you would use the Libraries API and you would also use the jQuery cycle plugin as part of creating a slideshow.
Instead of having a monolithic slideshow plugin that includes the jQuery cycle plugin, the Views Slideshow module knows how to use the Libraries API so that it can find the jQuery cycle plugin.
Approaching things in this collaborative fashion means that the jQuery cycle plugin is also available on the site for another module to use. This results in a smaller codebase on account of eliminating duplication of code across distinct monolithic plugins.
Additionally, the collaborative approach helps to eliminate the situation that I encountered when searching for slideshow on the WordPress official site. That search yielded over 500 results! Does a person really need over 500 different choices to create a slideshow? How is one supposed to choose?
Drupal's philosophy is that module developers should work together to create modules that are both small enough and extensible enough so that the situation of 500 slideshow plugins never arises.
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