Are the Dragon Quest games linked?

[Carmilla]

Ive heard that Dragon Quest 1-3 is its own little trilogy and so are 4-6.

So are 7 and 8 linked too? Or are they totally seperate games?
If ive never played part 7 will i be lost story wise if i start with 8?

[Captain Maxx Power]

Every DQ game can be played on it's own without any prior knowledge of the prequels. Mainly it's a case of the folklore of the previous games' events being alluded to (e.g. the main hero in DQ2 being decended from the main hero in DQ1). You don't need to have played the previous games to enjoy any of the others however.

[Zeromus_X]

I-III is the Loto Saga, and III is a prequel to I and II.

IV-VI is the Zenithian Saga, with that castle in the sky and what-not.

When DQ IX comes out, it might be connected to DQ VII and VIII, or they may not be connected through trilogies after that. Who knows.

[DJZen]

Basically you don't find out what the connection is until the third game in the trilogy. There's also some vague hinting that the series as a whole is interconnected (especially if you consider the Monsters series canonical, which wouldn't disrupt the storyline of the series in any way.)