Read-only memory in the context of Rompler

A CD-ROM (/ˌsiːdiːˈrɒm/, compact disc read-only memory) is a type of read-only memory consisting of a pre-pressed optical compact disc that contains data computers can read, but not write or erase. Some CDs, called enhanced CDs, hold both computer data and audio with the latter capable of being played on a CD player, while data (such as software or digital video) is only usable on a computer (such as ISO 9660 format PC CD-ROMs).

During the 1990s and early 2000s, CD-ROMs were popularly used to distribute software and data for computers and fifth generation video game consoles. DVDs as well as downloading started to replace CD-ROMs in these roles starting in the early 2000s, and the use of CD-ROMs for commercial software is now rare.

Punched tape or perforated paper tape is a form of data storage that consists of a long strip of paper through which small holes are punched. It was developed from and was subsequently used alongside punched cards, the difference being that the tape is continuous.

Punched cards, and chains of punched cards, were used for control of looms in the 18th century. Use for telegraphy systems started in 1842. Punched tapes were used throughout the 19th and for much of the 20th centuries for programmable looms, teleprinter communication, for input to computers of the 1950s and 1960s, and later as a storage medium for minicomputers and CNC machine tools. During the Second World War, high-speed punched tape systems using optical readout methods were used in code breaking systems. Punched tape was used to transmit data for manufacture of read-only memory chips.

Mac OS (originally System Software; retronym: Classic Mac OS) is the series of operating systems developed for the Macintosh family of personal computers by Apple Computer, Inc. from 1984 to 2001, starting with System 1 and ending with Mac OS 9. The Macintosh operating system is credited with having popularized the graphical user interface concept. It was included with every Macintosh that was sold during the era in which it was developed, and many updates to the system software were done in conjunction with the introduction of new Macintosh systems.

Apple released the original Macintosh on January 24, 1984. The first version of the system software, which had no official name, was partially based on the Lisa OS, which Apple previously released for the Lisa computer in 1983. As part of an agreement allowing Xerox to buy shares in Apple at a favorable price, it also used concepts from the Xerox PARC Alto computer, which former Apple CEO Steve Jobs and other Lisa team members had previewed. This operating system consisted of the Macintosh Toolbox ROM and the "System Folder", a set of files that were loaded from disk. The name Macintosh System Software came into use in 1987 with System 5. Apple rebranded the system as Mac OS in 1996, starting officially with version 7.6, due in part to its Macintosh clone program. That program ended after the release of Mac OS 8 in 1997. The last major release of the system was Mac OS 9 in 1999.

Game Boy Game Pak is the brand name of the ROM cartridges used to store video game data for the Game Boy family of handheld video game consoles, part of Nintendo's line of Game Pak cartridges. Early Game Boy games were limited to 32 kilobytes (KB) of read-only memory (ROM) storage due to the system's 8-bit architecture. Nintendo later incorporated a memory bank controller into cartridges to allow for more storage by switching between ROM banks. This change allowed Game Paks to reach 8 megabytes (MB) of storage, allowing for more complex games.

In addition to ROM, cartridges could also include random-access memory (RAM) chips that could be used for increased performance or to save game progress. A battery in the cartridge would keep the RAM powered when the Game Boy was off. Later cartridges could also include real-time clock functionality that could keep track of time even when the device was off or a Rumble Pak to add vibration feedback to enhance gameplay.

A Macintosh clone is a computer running the Classic Mac OS operating system that was not produced by Apple Inc. The earliest Mac clones were based on emulators and reverse-engineered Macintosh ROMs. During Apple's short lived Mac OS 7 licensing program, authorized Mac clone makers were able to either purchase 100% compatible motherboards or build their own hardware using licensed Mac reference designs.

During Apple's switch to the Intel platform, many non-Apple Wintel/PC computers were technologically so similar to Mac computers that they were able to boot the Mac operating system using various combinations of community-developed patches and hacks. Such a Wintel/PC computer running macOS is more commonly referred to as a Hackintosh. Apple's transition to Apple silicon means that making Mac clones is considerably harder.

A bootloader, also spelled as boot loader or called bootstrap loader, is a computer program that is responsible for booting a computer and booting an operating system. If it also provides an interactive menu with multiple boot choices then it is often called a boot manager.

When a computer is turned off, its software‍—‌including operating systems, application code, and data‍—‌remains stored on non-volatile memory. When the computer is powered on, it typically does not have an operating system or its loader in random-access memory (RAM). The computer first executes a relatively small program stored in the boot ROM, which is read-only memory (ROM, and later EEPROM, NOR flash) along with some needed data, to initialize hardware devices such as CPU, motherboard, memory, storage and other I/O devices, to access the nonvolatile device (usually a block device, e.g., NAND flash) or devices from which the operating system programs and data can be loaded into RAM.

A video display controller (VDC), also called a display engine or display interface, is an integrated circuit which is the main component in a video-signal generator, a device responsible for the production of a TV video signal in a computing or game system. Some VDCs also generate an audio signal, but that is not their main function. VDCs were used in the home computers of the 1980s and also in games consoles and arcade games.

The VDC is the main component of the video signal generator logic, responsible for generating the timing of video signals such as the horizontal and vertical synchronization signals and the blanking interval signal. Sometimes other supporting chips were necessary to build a complete system, such as RAM to hold pixel data, ROM to hold character fonts, or some discrete logic such as shift registers.

An application-specific integrated circuit (ASIC /ˈeɪsɪk/) is an integrated circuit (IC) chip customized for a particular use, rather than intended for general-purpose use, such as a chip designed to run in a digital voice recorder or a high-efficiency video codec. Application-specific standard product chips are intermediate between ASICs and industry standard integrated circuits like the 7400 series or the 4000 series. ASIC chips are typically fabricated using metal–oxide–semiconductor (MOS) technology, as MOS integrated circuit chips.

As feature sizes have shrunk and chip design tools improved over the years, the maximum complexity (and hence functionality) possible in an ASIC has grown from 5,000 logic gates to over 100 million. Modern ASICs often include entire microprocessors, memory blocks including ROM, RAM, EEPROM, flash memory and other large building blocks. Such an ASIC is often termed a SoC (system-on-chip). Designers of digital ASICs often use a hardware description language (HDL), such as Verilog or VHDL, to describe the functionality of ASICs.

A programmable read-only memory (PROM) is a form of digital memory where the contents can be changed once after manufacture of the device. The data is then permanent. It is one type of read-only memory (ROM). PROMs are usually used in digital electronic devices to store low level programs such as firmware or microcode. PROMs may be used during development of a system that will ultimately be converted to ROMs in a mass produced version. These types of memories are used in microcontrollers, video game consoles, mobile phones, radio-frequency identification (RFID) tags, implantable medical devices, high-definition multimedia interfaces (HDMI), and in many other consumer and automotive products.

PROMs are manufactured blank and, depending on the technology, can be programmed at the wafer, final test, or system stage. Blank PROM chips are programmed by plugging them into a device called a PROM programmer. A typical PROM device has an array of memory cells. The bipolar transistors in the cells have an emitter that is connected to a fuse called a polyfuse. To program a PROM is to strategically blow the polyfuses.

The Commodore PET is a line of personal computers produced starting in 1977 by Commodore International. A single all-in-one case combines a MOS Technology 6502 microprocessor, Commodore BASIC in read-only memory, keyboard, monochrome monitor, and, in early models, a cassette deck.

Development of the system began in 1976, and it was demonstrated and sold as the first personal computer for the masses at the January 1977 Consumer Electronics Show. The name "PET" was suggested by Andre Souson after he saw the Pet Rock in Los Gatos, and stated they were going to make the "pet computer". It was backronymed to Personal Electronic Transactor. In a 1995 retrospective, Byte magazine—and subsequently many others—referred to the PET, Apple II and TRS-80 collectively as the "1977 trinity" of pioneering personal computers.

A MAC address (medium access control address or media access control address) is a unique identifier assigned to a network interface controller (NIC) for use as a network address in communications within a network segment. This use is common in most IEEE 802 networking technologies, including Ethernet, Wi-Fi, and Bluetooth. Within the Open Systems Interconnection (OSI) network model, MAC addresses are used in the medium access control protocol sublayer of the data link layer. As typically represented, MAC addresses are recognizable as six groups of two hexadecimal digits, separated by hyphens, colons, or without a separator.

MAC addresses are primarily assigned by device manufacturers, and are therefore often referred to as the burned-in address, or as an Ethernet hardware address, hardware address, or physical address. Each address can be stored in the interface hardware, such as its read-only memory, or by a firmware mechanism. Many network interfaces, however, support changing their MAC addresses. The address typically includes a manufacturer's organizationally unique identifier (OUI). MAC addresses are formed according to the principles of two numbering spaces based on extended unique identifiers (EUIs) managed by the Institute of Electrical and Electronics Engineers (IEEE): EUI-48—which replaces the obsolete term MAC-48—and EUI-64.