sentences:  The SDRs used in HTM are binary representations of data consisting of many bits with a small percentage of the bits active (1s); a typical implementation might have 2048 columns and 64K artificial neurons where as few as 40 might be active at once.Although it may seem less efficient for the majority of bits to go "unused" in any given representation, SDRs have two major advantages over traditional dense representations.First, SDRs are tolerant of corruption and ambiguity due to the meaning of the representation being shared ("distributed") across a small percentage ("sparse") of active bits.