Computer Memory and Storage

RAM is volatile memory, meaning it requires constant electrical power to maintain stored data. When power fails, all data in RAM is lost permanently. Option B is incorrect because PC/XT used the 8088 processor, not 80186.

A cylinder is formed by the collection of corresponding tracks on all the recording surfaces of a hard disk stacked vertically together.

ADD with carry instruction will add the specified byte, either in a register or in the address contained by the H & L registers, and the value of the Carry bit, into the accumulator.

A floppy disk, also called a diskette, is a disk storage medium composed of a disk of thin and flexible magnetic storage medium.

Buddy Systems are used for splitting memory into different parts which is why it is used for implementing a memory management system.

Access arm moves the read/write head across the surface of the disk of a phonograph.

Swapping is a technique, which enables the computer to execute programs and manipulate data files larger than the main memory.

Magnetic disks have the highest access time among others, which is 50 to 150 nanoseconds.

ROM (Read-Only Memory) is 'essentially empty' in the sense that it contains no user-writable or changeable content - it's pre-programmed during manufacturing and cannot be modified by normal use. RAM can be written to, EPROM can be erased and reprogrammed, PROM can be programmed once. Only ROM is permanently fixed.

PROM (Programmable Read-Only Memory) can be written only once by the user using special equipment. After programming, it becomes permanent and non-volatile like ROM. RAM is volatile, ROM is pre-programmed, and EEPROM can be rewritten multiple times.

ROM (Read-Only Memory) is programmed during manufacturing and cannot be changed afterward. It contains permanent instructions and data that the computer needs to boot up. Unlike PROM, it's not user-programmable.

Cassette tapes use sequential access because data must be read in the order it was written - you must fast-forward or rewind to reach specific locations. Unlike disks, you cannot jump directly to any point on the tape.

RAM is volatile memory that loses its contents when power is turned off. ROM, EPROM, and PROM are all non-volatile storage types that retain data even without power.

Disk drives require protection from dust (can cause head crashes), sunlight (heat damage), and temperature extremes (AC rooms maintain optimal operating conditions). All precautions are equally important for disk longevity.

ROM (Read-Only Memory) is non-volatile and permanently stores data that cannot be modified under normal operation. RAM, EPROM, and EROM (though EROM is an unusual term) are either volatile or erasable.