What are the main differences between major PHP releases and how do they affect development?

The main releases of PHP differ in functionality, performance, and support for new language features. For example:

• PHP 5.x introduced support for OOP, exceptions, and improved database handling.
• PHP 7.x significantly increased performance, introduced strict typing, new operators, and syntax improvements.
• PHP 8.x added JIT compilation, union types, attributes, and improved error handling.

Impact on development:

• New versions allow writing cleaner, safer, and more efficient code.
• Using new features simplifies architecture and enhances readability.
• When updating, it is important to check code and library compatibility.

For example, in PHP 7, strict typing can be used:

declare(strict_types=1);

function sum(int $a, int $b): int {
    return $a + $b;
}

This helps catch errors during development.