Because almost all websites need the same basic components in order to be great.
Because it's insane to do any kind of software development without a good library.
This is best told as the evolution of a hobby site.
You want to build your own website. You'd like to start by posting some of your pithy commentary and build out from there. Polls, reviews, who knows?
There are a lot of kits out there to help you out, but they all kind of do the same thing: help you make a blog. Well, what if you want a bit more? What if you want to mix and match features — even build a whole new type of website? You may still need all the standard equipment these kits provide, but using them might seriously handcuff your creativity.
What you need is an honest-to-goodness website-building library. Period.
You need something that's designed from the get-go to be extendible, customizable and that doesn't make unalterable assumptions about what you want. On the other hand, it's got to provide all of the stuff you might need.
Let's walk through building your website without a library.
Maybe you want to be able to post a bunch of links on a page, or, better yet, write up stories or journal entries, blog-style. Ok, that shouldn't be too hard. Just pop the text in there and you're up and running.
You can't both update the same page at the same time; that's just asking for trouble. So, you need a place where you can add stories with a web form. You've got to make a form and make it validate the content.
So your site's getting users and they're noticing some typos. They're sending you emails, but would like to comment on the story directly. Now you've got to extend your form to support editing existing stories. You've also got to build in something that lets users make comments (but not create or edit stories).
You're getting fancier stories and you'd like to put in lists and images and other fancy formatting. No problem; you're entering your stories in raw HTML anyway. So are your users when they make comments.
You want to link in an image you made. You've got to attach it to the system somehow. Just FTP it up and dump it in a folder, then reference it. Easy. Don't forget to make a thumbnail.
Users think it would be cool to get notifications when a new story is posted. They don't think HTML emails are cool (too much junk and too many viruses).
Users think skinning the site is cool too; they're getting bored of your same old theme and layout. You want to get fancy with CSS, but you need to first figure out which browser you're targeting.
Your stories are getting bigger, but you don't always have time to write it and post it. You're saving stuff on your desktop in text files before posting.
You've got quite a few stories now and it's getting harder to find stuff. You'd like to be able to find all the stories you've created. In the last month. Of a certain topic. It would be nice to split stories into different sections, so users can more easily find what they want.
The site's humming along and you want to make a registered-user only area. There are also some private areas for editors and premium users/subscribers. You'll need to make some sort of user groups just to keep it manageable. You need to define who gets to do what.
MySQL seemed like a good choice at first, but its full-text search isn't doing it for you. You'd like to flip to a different database and see how that works.
And, finally, the killer...
Now you think you'd like to open up a site for game reviews. You can't just start simple, can you? You've got to have all of the same features as your story site, right up front. Too bad the code for your story site just kind of grew and isn't all that refactorable.
Time to start copy/pasting...
Focus on your own application's features, not a web application's features.
When you think about making a website, you know exactly what you want. You want everything, but you don't have the time (and maybe not the skills) to do it. So you skip it all and put up something fast. It works for a while, but you have to spend way too much time on details instead of adding more application-specific functionality.
When you start with an earthli WebCore application, you've already got an enormous base of software on which to build. You can focus on things that make your application special instead of rushing to catch up with all of the features that make your application great.
Don't let the limited reusability of other products define your application.
You may have noticed that the product we built above exists already. It's called SlashCode or PHPNuke or Mambo. Bulletin boards like PHPBB, vBulletin and other do those things too. They also have a lot of other bells and whistles, but most of these products are really domain-specific. What if you want to make a photo-album manager (just off the top of my head)?
That's what the earthli WebCore offers: you get to reuse code for similar tasks in vastly different applications. What's more, with a clean separation between application and library code, if a new, advanced feature like moderation is added (a la Slashdot), it can be written generically and made available for any WebCore application that wants to use it.
It's not just theory — it really works.
Two of them, News and Recipes, are relatively thin layers: they don't add to the base functionality of the WebCore very much at all. Looking at the code, you see that these applications mostly focus laser-like on defining the UI for the application. The core logic is already in place, so you're free to define properties and decide how the app's going to look.
Albums and Projects are larger applications, adding a lot of properties and utilizing multiple object types within one application, journals and pictures in Albums and changes, jobs, components, branches and releases in Projects. At each point, the application only contains code to define features specific to its problem domain. Projects doesn't need to implement threaded commenting. The WebCore's already got that covered.
On the other hand, the WebCore is fully object-oriented (as far as PHP 4.x allows), so it's not a big deal to create a customized comment object for an application and link that in instead. If you need more properties, you just define them in a descendent class and tell your application to use that class instead when creating/editing/storing comments. Find out more in customization.
Websites are software. Writing HTML may not be programming, but making a good website today sure is. While PHP is free, fast and pretty easy to use, it doesn't deliver the tools you really need to make a great website. If you use only PHP to build your site, you've got a long hard slog ahead of you.
Do yourself a favor and try out the earthli WebCore. You'll be glad you did.
Still not convinced? Read more about earthli WebCore's extensive features.