I'm not a guitarist, i'm learning piano and i'm trying to translate some guitar tab for piano.

With eg this section of tab (for I Don't Want It by Ween, from the Ultimate Guitar site):

e--8-8-8---3-3----3-3-3-3-3-3---4-4--|
B--9-9-9---4-4----4-4-4-1-1-1---4-4--|
G--8-8-8---3-3----3-3-3-1-1-1---x-x--|
D-------------------------------3-3--|
A-------------------------------4-4--|
E------------------------------------|

At the start, the D A & E strings just have a "-". Does that mean you don't play those strings, or does it mean you play them open?

Sometimes i've seen tab where the open strings are represented by having a "0", but I'm guessing that the convention may be to omit these as it makes the tab too cluttered and hard to read. Later on in that tab section there's an x on the G string, which i'm guessing means to mute the string.

That kind of suggests that we are supposed to play the E, A and D strings at the start, otherwise they would have x's too? But i think this is one of those things that is ruled by convention rather than logic necessarily.

I'm not a guitarist, I'm learning piano and I'm trying to translate some guitar tab for piano.

With this section of tab (for I Don't Want It by Ween, from the Ultimate Guitar site):

e--8-8-8---3-3----3-3-3-3-3-3---4-4--|
B--9-9-9---4-4----4-4-4-1-1-1---4-4--|
G--8-8-8---3-3----3-3-3-1-1-1---x-x--|
D-------------------------------3-3--|
A-------------------------------4-4--|
E------------------------------------|

At the start, the D A & E strings just have a "-". Does that mean you don't play those strings, or does it mean you play them open?

Sometimes I've seen tab where the open strings are represented by having a "0", but I'm guessing that the convention may be to omit these as it makes the tab too cluttered and hard to read. Later on in that tab section there's an x on the G string, which I'm guessing means to mute the string.

That kind of suggests that we are supposed to play the E, A and D strings at the start, otherwise they would have x's too? But I think this is one of those things that is ruled by convention rather than logic necessarily.