Floating gate = the switching element on a transistor acts as a capacitor and can hold charge. the basic primitive for building flash memory. NAND SSDs which a

Floating gate = the switching element on a transistor acts as a capacitor and can hold charge. the basic primitive for building flash memory. NAND SSDs which are common today are essentially rows of similar structures. Each row is a string of floating gate transistors, and to read a single bit, you gotta run the whole operation of reading the entire row. Random access means that you can read anything anywhere without any sort of similar caveats.