Gambits. What to do against them?

The best way is to take them.

it depends on the gambit---what to do.

I think you have some trouble with opening traps, not with gambits. The best way to completely avoid them is doing unusual things. The old Benoni defence maybe is a bad opening, but throws your opponents out of theory so they can't do any gambits.

The Old Benoni is in itself a gambit. But other than that, it's quite playable if you want a closed position... no matter who takes the pawn or who defends it.

Good point.  I guess the question is: when we do know if it's a gambit or a trap!

In another thread, after I mentioned that most of the traps of which I am vaguely aware are off of 1 d4, someone pointed out to me that three well known traps (not that I can remember them right now -- Englund was one) against 1 d4 all involve black playing ...e5.  

(yes, there are refutations, obviously, but this is for folks who haven't learned them yet)

So, for those who want to make a general rule of "take the first pawn, but not the second", might want to change it to: "take the first pawn but not the second -- but don't even take the first pawn if it's d4xe5" ?

I don't think this makes much sense. In the Englund (1. d4 e5) and in the Budapest (1.d4 Nf6 2. c4 e5) you should definitely take. What else?

For example, in the Englund 1. d4 e5 2. dxe5 Nc6 you can play just about anything (like Nc3) and you are fine. You can also go into the main line, but that is dangerous if you don't know what's going on.

I also think that thinking about openings is not very profitable for anyone under 2000.

In the Englund, there's a deadly trap when taking the pawn. I'm quite sure there are multiple, some leading to checkmate, some costing a rook or a bishop.

Those are all on the main line, several moves in. That is why I suggested to deviate early (on move 3 or maybe 4), and go into a quiet sideline giving back the pawn.

You are sort of being contradictory here.  For one, you are suggesting openings are not very profitable for those under 2000, but then you write:

Those are all on the main line, several moves in. That is why I suggested to deviate early (on move 3 or maybe 4), and go into a quiet sideline giving back the pawn

So, how is a person to even know what's the mainline for that so that he knows that he's deviating?  In fact, I was suggesting alternative advice for someone who knows almost nothing about openings, which is "don't take the pawn" (in a 1 d4 e5 situation).

^I agree, without knowing what to do in specific openings I would never have passed even 1000

Right -- so, there are three (very broad) categories here:

1.  Learn opening principles, no need to know openings

2.  Start to learn the first 2-4 moves of the popular openings (and *why*), avoiding traps, etc

3.  Picking an opening you like and starting to learn its theory

I can see players even at, say, 900-1000 beginning to move into step 2 here.

Thoughts?

900-1000 I was still step 2, only started learning theory after 1100-ish. Opening "principles" really only gets you to maybe 900, there's no way you're going to get better as a player if you dont know why you play a move in the opening

1) Queen's Gambit shouldn't be on your list. It's not really a gambit.

2) The classical way to handle a gambit is to accept the sacrificed Pawn (especially if it's a center Pawn) and later on to return it, after the opponent has made some efforts to recover it. The time that your opponent spends recovering his sacrificed Pawn should allow you to catch up in time and development.

1. Well it kind of is, because black can still hold on to the pawn. In fact, I found this cool variation of the queen's gambit accepted where black holds on to the pawn and makes it hard to develop for white but sacrificing a rook. To my surprise black actually isn't lost at all

2. Not really. Like for the king's gambit, accepting the gambit and giving back the pawn gives white a bigger lead in development and a better center control. And gambits like the smith morra, it's not really possible to give back the pawn with an advantage 

Upwards of 1100 blitz or 1200 rapid here it becomes quite reasonable to develop a repertoire and learn theory, but not (just) as a series of moves, but as a series of positions and patterns.

I say that (1)  is a must even for beginners.

As for (2), it happens automatically if you watch chess videos, read articles, books, etc. No need to actively study anything. Watching videos is more fun than studying something, right?

As for (3), anyone can certainly try if they want... but for a low rated player it will not be nearly as beneficial as you might think. Studying middlegames and tactics puzzles have huge benefits, while studying openings has marginal benefits.

Well put.  Yes, I think step 1 is the very first thing that a player should do.

This three-stage list is in the context of openings only.  @magipi is correct about tactics -- I would add one should begin to study tactics as you finish step 1 (and I agree with tactics puzzles here are very useful).  Do step 2 in opening and learn tactics at the same time.

I would also add, when a person is deeply into step 2 and/or dipping a toe into the water in step 3, one can begin to learn openings on a deeper level *during* a daily game -- i.e., learn the very opening you are playing with the chess database here (figure out your move, see what the masters play, if they play something different try to understand why -- or perhaps watch a good video on the opening you're playing, etc.)

Which reminds me to add: playing 10-minute or faster games may be fun, but it's harder for a beginner to learn very much from them.