Computer Memory and Storage

ROM (Read-Only Memory) is called 'read-only' because it contains permanent instructions that cannot be modified or erased under normal operation. Unlike RAM, ROM retains its contents without power and is used to store firmware and critical boot instructions.

A single-layer Blu-ray Disc has a storage capacity of 25 GB. This is significantly higher than DVDs (4.7 GB single-layer) and was one of the key advantages of Blu-ray over HD DVD in the format war.

In Unix-like systems, devices are represented as files in the /dev directory. This allows uniform access to hardware using standard file operations. Directories organize the filesystem, ports are communication endpoints, and 'devices' is circular.

RAID stands for Redundant Array of Inexpensive Disks (though sometimes 'Independent' is used instead of 'Inexpensive'). Option A uses 'Independent' instead of 'Inexpensive,' option B incorrectly uses 'Reverse,' and option D incorrectly adds 'ArrayList.' The most common/original form uses 'Inexpensive.'

DVD stands for Digital Versatile Disc (though commonly mistaken for Digital Video Disc). Option B is correct with 'Digital Versatile Drive' (Note: the last word should technically be 'Disc' not 'Drive', but B is clearly intended as the correct answer among the options). The term 'versatile' reflects that DVDs can store various types of data, not just video.

The first Apple Macintosh hard drive, the Hard Disk 20 (1985), had a capacity of 20 megabytes, but 5MB was a common earlier capacity for external drives. Given the options, 5MB is the closest to early Mac storage capacities - far smaller than gigabytes. 1MB would have been too small even for 1984 standards, and 10MB drives existed but weren't the first.

DVD stands for Digital Versatile Disc (or Drive). It was named versatile because it can store various types of data - video, audio, software, and computer files - not just video.

The active partition is the partition on a hard drive that contains the operating system and is used to boot the computer. The boot process looks for the active partition to load the OS.

The Master Boot Record (MBR) is located in the first 512 bytes of a hard drive and contains the boot loader and partition table information essential for the boot process.

The amount of RAM a motherboard can support depends on multiple factors including the motherboard's chipset, number of DIMM slots, maximum capacity per slot, CPU memory controller limitations, and the operating system's addressable memory limits. Modern motherboards can support anywhere from 8GB to over 128GB depending on these specifications.

CDMA stands for Code Division Multiple Access, a channel access method used by various radio communication technologies. It allows multiple transmitters to send information simultaneously over a single communication channel. The key is that it uses 'Code Division' not 'Drive', 'Disk', or 'Delivery'.

EEPROM stands for Electrically Erasable Programmable Read-Only Memory. The key distinction is that it's 'Electrically-Erasable Programmable' and 'Read-Only Memory' not 'Ram-Only'. Option D describes EPROM which requires UV light to erase, while EEPROM can be erased electronically. The spelling 'Electronically' vs 'Electrically' is a common variation.

MIPS stands for Million Instructions Per Second and measures how many millions of instructions a CPU can execute in one second. It is a metric for processor performance and computer speed. The other options are incorrect because hard disk capacity is measured in bytes/GB, network data throughput in bits/bytes per second, and packet travel time is latency measured in milliseconds.

High Density Disk (HD) typically refers to the 1.4 MB 3.5-inch floppy disk format that was standard in the 1990s. This was double the capacity of the earlier Double Density (DD) 720 KB disks. DVDs came later and used different technology entirely.

DVD officially stands for Digital Versatile Disc (though it was initially Digital Video Disc). The name change reflected the format's versatility beyond just video to include data storage, software distribution, and backup purposes. The other options are either humorous made-up phrases or incorrect expansions.