PHP classifies errors by severity — fatal errors halt execution, warnings indicate something is likely wrong, and notices flag potential problems that may not break your script. Each entry below covers the most common PHP engine errors with copy-paste fixes.

Error Codes

ErrorDescriptionFix
Fatal ErrorUncaught error, out of memory, or undefined function call that halts executionEnable error reporting, add try/catch blocks, and increase memory_limit in php.ini
Notice: Undefined IndexAccessing an array key that does not existUse isset() or the null coalescing operator ?? to check before accessing
Parse ErrorSyntax error caught before execution — missing semicolons, unmatched bracketsReview the reported line number, check for typos, and use an IDE with syntax highlighting

Quick Debug

// Show all errors during development
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);