PHP duwe rong sistem parallel kanggo masalah: errors tradisional (warnings, notices, fatal errors) lan exceptions (berbasis obyek, bisa dicegah karo try/catch). PHP modern nggabungake akeh saka iki ing hirarki Throwable, lan praktik apik milih exceptions.
Tingkat error tradisional
E_NOTICE → minor issues (e.g. using an undefined variable) — script continues
E_WARNING → non-fatal problems (e.g. include of a missing file) — continues
E_ERROR / Fatal → serious errors (e.g. calling an undefined function) — script HALTS
E_DEPRECATED → use of deprecated features
