ECC stands for error correcting code and is primarily used for servers. So why does it matter for consumers? Torvalds points out that the lack of ECC support on Intel's consumer platforms results in lower security. Torvalds basically suggests Intel's marketing decisions have held back adoption of a technology that would make PCs more secure and more stable:
"ECC absolutely matters," retorted Torvalds. "Intel has been detrimental to the whole industry and to users because of their bad and misguided policies wrt ECC. Seriously. And if you don't believe me, then just look at multiple generations of rowhammer, where each time Intel and memory manufacturers bleated about how it's going to be fixed next time... And yes, that was – again – entirely about the misguided and arse-backwards policy of 'consumers don't need ECC', which made the market for ECC memory go away."Full details at The Register.