When do you use про and when о?

Question

When do you use про and when о? (about). Are they synonyms in all contexts?

EDIT: I discovered Usage of "про" instead of "о"

Apologies!

Answer 1

There's a slight difference in meaning. "О" implies a more extensive discussion of the topic, and "про" has a connotation of "touching upon" a certain theme.

Он рассказал мне об этой книге.

He told me about this book (what it's about, who the main characters are, etc.).

Он рассказал мне про эту книгу.

He told me of this book (could you say it like that in English?), mentioned it (told me that it exists and said the title).

At the same time, both sentences can be translated as "He told me about this book". The difference is very subtle, so "о" and "про" are usually interchangeable.

In written speech (for example, book annotations), "о" is generally more appropriate, and "про" is more lightweight and is used mostly in spoken conversation.

Answer 2

They are basically complete synonyms, but "про что-то" is mostly used in conversation or when imitating actual speech, while "о чём-то" is stylistically more neutral. Also note that "о чём-то" takes a different case.

Answer 3

Про is used with the accusative case - написать про кого, что? - написать про картину, написать про актрису. О is used with the prepositional case - написать о ком, чём? - написать о книге, написать об актрисе.

One subtle grammatical difference is that о should be written об when followed by a word beginning with a vowel почитал о картине, but почитал об актрисе.

They also imply some emotions, which are not easily logically explained. I guess, because people of higher education or/and of a more poetic nature tend to use о instead of про. When you say:

Они разговаривали о любви

(They spoke about love) it sounds different than when you say:

они разговаривали про любовь.

The latter implies a love with a lower intensity, like dating etc. On the other hand про is more business style.