vorab
in advance
Ahead of time, before something else happens or begins.
Ich schicke Ihnen die Agenda für das Meeting schon einmal vorab per E-Mail.
I'll send you the agenda for the meeting in advance by email.

in advance
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in advance
Ahead of time, before something else happens or begins.
Ich schicke Ihnen die Agenda für das Meeting schon einmal vorab per E-Mail.
I'll send you the agenda for the meeting in advance by email.

The adverb 'vorab' (in advance) is a compound of 'vor' (before) and 'ab' (off/from). It literally means that something happens before another action or event.
Könnten Sie mir die Unterlagen vorab zukommen lassen?
Could you send me the documents in advance?
'Vorab' (in advance) can appear flexibly in the sentence. It often stands at the beginning of the sentence, in which case the verb follows in second position, or it appears in the middle of the sentence.
Vorab möchte ich mich bei allen für die Teilnahme bedanken.
First of all, I would like to thank everyone for participating.
The word is often used with verbs of communication. Typical combinations are 'vorab informieren' (to inform in advance), 'vorab besprechen' (to discuss in advance), or 'vorab zusenden' (to send in advance).
Lassen Sie uns die Details vorab per Telefon besprechen.
Let's discuss the details by phone in advance.
beforehand
'vorher' and 'vorab' both mean that something happens before another point in time. 'vorher' is very general and fits almost any everyday situation: you do one thing first and then something else afterward. 'vorab' sounds a bit more planned or official. It is often used when you give information, money, documents, or a message in advance, before the actual matter begins. Learners may confuse the words because both mean 'before that' in terms of time. As a simple guide: use 'vorher' for normal sequences, and 'vorab' for something you do or communicate in advance.

Mein Nachbar bezahlt die Ware vorab, damit sie am Wochenende geliefert wird.
My neighbor pays for the goods in advance so they will be delivered on the weekend.
Vor dem Film habe ich vorher noch schnell die Nachrichten gesehen.
Before the film, I quickly watched the news beforehand.