Updating WordPress Tips and Techniques - WordPress website development mistakes
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What is the point of clearly illustrating the differences between WordPress core files and theme files? What relationship does this have to updating WordPress?
The answer is: “You should only be editing your theme files and plug-in files in order for you to easily update WordPress in the future.”
This is why you should know what and where your core and theme files are, so that when you start working on developing your own WordPress website, you will never edit the core files.
If you edit the core files, then all of your changes will be lost once you update WordPress, and you will edit those core files again (like those files that belong to the wp-includes directory). If you edit those cores files, it now seems very impractical to update WordPress. This is why a majority of WordPress websites nowadays are still not being updated, due to the fear of serious website malfunction, because their core files have been substantially edited.
One common question asked at this point is “If editing WordPress core files is a mistake, then how will I be able to obtain a certain functionality for my website that is not included in both core and theme files?”
The short answer is to install a plug-in that serves that functionality. This is why WordPress plug-ins exist; they perform certain functions without forcing you to edit WordPress core theme files. The down side is, what do you do when you want a difficult functionality that no plug-in offers yet? Then you can request help in this section: http://wordpress.org/extend/ideas/
To prevent website functionality problems during a WordPress update, it is important that during the development stage of your website, you should ONLY edit your WordPress theme files (see below) and add plug-ins to add some unique functionality that is required:
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