The Queen's Gambit has been around for at least 500 years. There are a plethora of variations attached, that in the main, fall into two distinct categories. They are QG Accepted and QG Declined.
For a long time this particular system was not especially common in top-level chess as the closed openings did not lend themselves to explosive attacking games right from the off.
When Steinitz and later Tarrasch developed the concept of positional play it underwent a renaissance and, due to it's endgame possibilities, became extremely popular. It has receded since it's zenith in the 20s and 30s but is still used by masters from time to time.
The Latvian Gambit got it's name when it was extensively analyzed by some Latvian players early in the 20th century. It is considered unsound at the highest level because perfect or even solid play gives White a better game than Black.
However there is a flip-side and it's this. The Latvian Gambit is extremely complicated and has lots of possible lines, many of these leading to promising situations for Black.
Many players below master level and indeed some masters are not familiar with the maze of variations that arise from this gambit so it could be a useful weapon in your arsenal and you may be able to score some good victories with Black using it's variations.
The Smith Morra Gambit is named after Frenchman Pierre Morra and American Kenneth Smith, both of whom studied it thoroughly. It is used by White to counter the Sicilian Defense by Black.
People are split on who has the better line, White on the Smith Morra or Black on the Sicilian. One thing for sure is that there is plenty of theory to cover on the Smith Morra as there are plenty of roads this one can take you down.
The Smith Morra is well worth a look if you're a 1.e4 player and you're sick or those smug Sicilian fans! It's probably as successful as 2.Nf3 at club level.
The Blackmar-Diemer is a variation of the earlier Blackmar Gambit named after Armand Blackmar. The Blackmar-Diemer gets it's name from German master Emil Josef Diemer who analyzed the opening and wrote a book on it in the 50s.
This is an aggressive opening option for White. There is an entire legion of club players who have fallen in love with it. It's not hard to see why. White sacrifices a pawn and what does he get? Well he gets a big lead in development and powerful attacking opportunities.
It must be said that it's not popular at grandmaster level as there are holes in it that Black can exploit and use to gain dominance. But at lower levels the Blackmar-Diemer can give White a good game.
The Vienna Gambit is so named because it was first played in the mid-nineteenth century by a Swiss guy called Carl Hamppe. The thing was though he worked as a government official in Vienna, Austria and used to play a lot of his games there.
This is essentially a delayed King's Gambit with the Queen's Knight developed to c3 on the second move and the f-pawn offered as a sacrifice with 3.f4.
This is a gambit of it's time, aggressive as was the style at that time. The idea behind this is to give White the chance to pressurize Black's soft center down the bishop's file at f7. It is generally believed to lead to equality with best play from both sides.
The Reti Gambit was introduced by Richard Reti in the 1920s. It is designed to counter the French Defense. White plays the King's pawn up to tempt the Black Queen's pawn to capture it, effectively ripping the head off the French Defense.
This one will take you down some novel positions and may disorientate your opponent. Reti himself stunned the mighty Capablanca with his hypermodern inventions. So if his ideas could throw someone like Capa what chance for your friends down the club!
There are several possibilities for the Reti and there is a lot of theory attached. But if you do your homework and get familiar with the main lines, you will have a real gem, especially below master level.