Electronic signals are stored on a chip called NAND 

Electronic signals are stored on a chip called NAND Flash memory without the use of magnets to store data. The way SSDs work is a bit like RAM. RAM uses memory chips called volatile memory, which disappear when the power is turned off. SSDs use memory chips that are stored even when the power is off, called non-volatile memory. Because it is stored as an electronic signal, data storage, It reads faster and is a major difference with HDDs.

In the early 1950s, 1970s and 1980s, SSD-like technology was used only on high-end supercomputers. However, it was very expensive and the storage capacity was only 2MB ~ 20MBs, so it was not available to everyone until 1990. It was mainly used in military technology and space exploration. In the early 1990s, with the advent of technology, SSD prices plummeted. But age and size are still an issue.