When do you use γιατί or επειδή to mean because? Is one more common?

Question

When do we use γιατί or επειδή to mean because?  Which one of the two is more common?

Answer 1

Hello

If the causal sentence (= the sentense which starts with "επειδή" or "γιατί") comes after the main clause,  "επειδή" or "γιατί" can be used interchangeably. "Επειδή" is a bit more formal than "γιατί." "Γιατί" is  more common in oral speach, because it is shorter (γιατί"has 2 syllables, "επειδή" has 3 syllables")

Example:

Δεν ήρθε επειδή είχε δουλειά. = He didn't come because he was busy.

Δεν ήρθε γιατί είχε δουλειά. = He didn't come because he was busy. (less formal)

But:

Επειδή είχε δουλειά, δεν ήρθε. = Because he was busy, he didn't come.

In this phrase we cannot put "γιατί" instead of "επειδή."

When "γιατί" is the first word of a phrase, it always means "why"

Example:

Γιατί δεν ήρθες; = Why you didn't come?