Category: OOP

Load classes automatically with spl_autoload_register or Composer PSR-4.

Follow PHP-FIG PSR standards for interoperable modern PHP code.

Throw and catch exceptions to handle errors cleanly in object-oriented code.

Learn the five SOLID principles that guide maintainable object-oriented design.

Check an object’s type with instanceof before calling type-specific APIs.

Expose controlled read/write access to private properties.

Pass dependencies into classes instead of creating them internally.

Prefer composition (“has-a”) over deep inheritance (“is-a”) for flexible designs.

Understand how objects relate: association, aggregation, and composition.

Create object copies with clone and customize cloning via __clone.