sentences:  The most common error-correcting code, a SECDED Hamming code, allows a single-bit error to be corrected and, in the usual configuration, with an extra parity bit, double-bit errors to be detected.Recent studies give widely varying error rates with over seven orders of magnitude difference, ranging from , roughly one bit error, per hour, per gigabyte of memory to one bit error, per century, per gigabyte of memory.The Schroeder et al.