Picked this up at a local used bookstore, can anyone tell me more about it?

I’m can’t read a single word of Hebrew, but it was too beautiful a book to pass up. A cursory google image search reveals it’s a siddur avodat but I’m not entirely sure what that means or what the religious significance is.

Any information you can give on publishing date, the significance of it, or just a link to a good place to read more about it would be much appreciated!