Our current commercial information storage media include hard drives, USB flash drives, DVD discs, etc., but these cannot preserve information completely for a long time, at most for decades. Nowadays, most historical information is still stored in paper records, but this is inconvenient and difficult to find. Recently, Japans Hitachi Company developed a piece of quartz glass that can store data permanently and securely. It is only 20mm square and 2mm thick. The data is burned into the modified molecular arrangement structure in binary form by laser, and the data inside can be read by ordinary optical microscopes. This special quartz glass can store 40MB of data per square inch, which is a little larger than an ordinary CD, but there is still room for expansion. It is also fire-proof, radiation-proof, and waterproof, and has very good stability. It can ensure that data is completely preserved for two hours without being destroyed at a high temperature of 1,000 degrees. It is very suitable for use in government agencies, historical document collections, and other places.
