It's the Grand Prix variation. Often people avoid the direct 2. f4, because it allows d5. They put in 2 Nc3 first to prevent that, but then it starts to drift toward the Closed Sicilian lines.
Sicilian Defense F4 line?

As DrSpudnik said, this move order often leads into the Grand Prix variation after something like 2...Nc6 3.Nc3. The Grand Prix variation is a perfectly respectable sideline, often adopted by players who want to avoid all the opening theory in the main line Sicilian; I often play it myself.
Many players avoid 2.f4 and play the move oder 2.Nc3 Nc6 3.f4. This is to avoid the Tal Gambit, 2....d5 3.exd5 Nf6. Where Black gets a lot of play for the pawn. I would give that a try
thanks for the feedback. For one, F4 doesn't really call my attention too much, i don't like the open king side. I do like the D5 line you told me about though, would this be a correct variation? :

4...e6 5.dxe6 Bxe6; this is why ppl play 2.Nc3 first.
And about the Grand Prix (2.Nc3 3.f4) being a good counterattack for white:
The Open Sicilian is better for that...the reason ppl pick the Grand Priz is to avoid theory.

To Rothkevin:
In the variation you gave, after 4.c4 I would prefer 4...e6, continuing to break open white's center. After 5.dxe6 Bxe6, Black has a lot of development and play for a mere pawn
yup you're right. By the way, do you think 3......Qxd5? is good? although black loses a tempo, he destroys white's center.
It could be that white is scared or it could be that white likes the 41.5% winning rate that it gets from the position (after 2. Nc3 d3. 3. f4).

"I'm not a Sicilian player, but when White plays some variant like the Gran Prix Attack, which was known to be ineffective half a century or more ago, it tells me he is afraid of my Sicilian."
I would have said "his sicilian (if he plays d4)" rather than "my sicilian".
Why ? Hey, black wants 1) an open c column 2) a central majority, do you really think anyone is happy to play d4 and give you what you want so much ?
Possibly helpful:
Experts on the Anti-Sicilian by Jacob Aagaard & John Shaw (ed.) (2011)
https://web.archive.org/web/20140626195254/http://www.chesscafe.com/text/hansen147.pdf
Fighting the Anti-Sicilians by Richard Palliser (2007)
https://web.archive.org/web/20140627130915/http://www.chesscafe.com/text/hansen106.pdf
Anti-Sicilians: A Guide for Black by Dorian Rogozenko (2003)
https://web.archive.org/web/20140627050549/http://www.chesscafe.com/text/hansen50.pdf
Sveshnikov vs. the Anti-Sicilians by GM Evgeny Sveshnikov (2014)
Starting Out: Sicilian Grand Prix Attack by Gawain Jones (2008)
https://web.archive.org/web/20140627012235/http://www.chesscafe.com/text/hansen111.pdf
The Grand Prix Attack by Evgeny Sveshnikov (2013)
https://web.archive.org/web/20140626232217/http://www.chesscafe.com/text/hansen171.pdf
Grandmaster Repertoire: Beating the Anti-Sicilians by Vassilios Kotronias (2015)

It could be that white is scared or it could be that white likes the 41.5% winning rate that it gets from the position (after 2. Nc3 d3. 3. f4).
^^^!!
can someone tell me why white would do this?
specifically, what is the advantage in doing this as opposed to another move?


again a GM or his counterpart lost or drew a lot of games by playing the Chigorin as well as f4 as black or white

Grand Prix Attack is a very practical way to fight against sicilian.
It is also very theorical and there is nothing wrong with it.
It is far more subtle than most think and if u master it, u can easily outplay your opponent, even titled players.
The only problem is that u can't play GP attack against any set up (2...a6 for example), so white has to be able to transpose into something else in some lines. For example, GPA and closed sicilian are be very complementary, constituting a very good repertoire against sicilian.

Grand Prix Attack is a very practical way to fight against sicilian.
It is also very theorical and there is nothing wrong with it.
It is far more subtle than most think and if u master it, u can easily outplay your opponent, even titled players.
The only problem is that u can't play GP attack against any set up (2...a6 for example), so white has to be able to transpose into something else in some lines. For example, GPA and closed sicilian are be very complementary, constituting a very good repertoire against sicilian.
I play closed sicilian but not GPA, how do I use them complementary?

Fighting the Sicilian With The Grand Prix Attack...
https://www.chess.com/blog/RussBell/fighting-the-sicilian-with-the-grand-prix-attack
I recently saw this variation when my oppenent played it against me. i am not familiar with it so i want to know how to play against it. Also, is it even worth playing for white? a good counterattack?