Glass vs. Metal

Ok, here's a question I've been pondering about recently...I wish I knew the answer.

Glass breaks easily, but metal does not...why?

I was thinking that it might be due to the fact that glass is made of silicon and oxygen (right?), which forms a covalent bond and metals usually have ... different bonds? I was thinking that covalent bonds are somehow less strong than metal bonding...I don't know why though.

I was also wondering whether ionic bonds are stronger or weaker than covalent bonds...