Object-Oriented PHP

Where to Go from Here

We've touched on three topics central to OOP: classes, access modifiers, and inheritance. Classes define objects, access modifiers determine how objects can be used, and inheritance makes it easy to adapt objects for different circumstances. I've emphasized the ways in which procedural programming is like OOP with a view to easing the transition to an OO approach, but I've also shown important differences. A data type like a class, which incorporates functions, is unlike anything encountered in procedural programming. Additionally, OOP provides access modifiers to control how an object may be used. Instead of relying on documentation and a disciplined approach, OOP incorporates constraints into the language.

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