2.1.2+Describe+Primary+Memory

Distinguish between random access memory (RAM) and read-only memory (ROM), and their use in primary memory.


 * < RAM ||< ROM ||
 * < Stands for Random Access Memory ||< Stands for Read Only Memory ||
 * < Volatile - when power is switched off the memory empties. ||< Non volatile - when power is switched off the memory is retained ||
 * < Very fast read/write speeds. ||<  ||
 * < RAM acts as temporary storage for the operating system and running applications. ||< ROM stores the instructions and data that won't change. It stores the instructions that the computer needs in order to boot up. It also stores the instructions the computer needs to read input and write output. ||

**RAM**
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 * Data can be written to and read from memory very quickly
 * RAM acts as temporary storage and working space for the operating system and its applications
 * RAM takes the form of integrated circuits

**Addressing RAM**

 * Each location in memory has a unique address
 * Data stored in memory is organised into bytes
 * Memory locations start at 00000000
 * **Address** || **Memory Data** ||
 * 00000111 || 10100010 ||
 * 00000110 || 01010011 ||
 * 00000101 || 10101001 ||
 * 00000100 || 00011011 ||
 * 00000011 || 10101101 ||
 * 00000001 || 10011110 ||
 * 00000000 || 11101110 ||

**ROM**

 * Read Only Memory (ROM) is used to store instructions and data that will "never" change
 * Typically, ROM contains instructions that control how a computer starts up, reads input, and writes output (BIOS)

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