Computer Input and Output Devices

Study Notes

Physical devices for data entry include keyboards, touch screens, styluses, and virtual keyboards.
Common pointing devices are mice, touch pads (trackpads), and game controllers.
For image input, devices such as digital cameras, camcorders, mobile device cameras, flatbed scanners, and webcams are widely used.
Sound input is commonly achieved through microphones paired with voice recognition software, along with various sensor technologies.

Output devices transmit data from computers in forms such as text, images, sounds, and video.
Monitors, printers, and speakers/headphones are typical output devices.
Display screen types include Liquid Crystal Display (LCD), Light-Emitting Diode (LED), and Organic Light-Emitting Diode (OLED).
Key features of display technology include pixels, aspect ratio, and resolution for visual display quality.
Speakers provide sound output, with options for surround sound and wireless systems, while earbuds can pose a risk of hearing damage from excessive volume.

Inkjet printers are affordable, produce high-quality color prints, and operate quickly and quietly.
Laser printers offer faster speeds and higher-quality prints, but are generally more costly.
Cloud-ready printers can connect to the internet, while all-in-one printers combine printing, scanning, copying, and faxing capabilities.
Large format printers specialize in oversize image printing, and 3D printers create three-dimensional objects.

The motherboard contains the CPU, ROM, RAM, cache, and slots for expansion cards, such as sound/video cards and network interface cards (NIC).
The Central Processing Unit (CPU) is the "brain" of the computer, controlling functions and processing commands at speeds measured in gigahertz (GHz), which indicates billions of tasks per second.

CPU performance metrics include processor speed (measured in hertz, with gigahertz being a common standard) and the number of cores, ranging from single to multi-core configurations (dual, quad, and more).

Local storage devices like Hard Disk Drives (HDD) are nonvolatile and include internal and external drives, while Solid-State Drives (SSD) provide faster access speeds.
Portable storage options encompass flash drives and memory cards.
Cloud storage allows file access via the internet, often with a free tier available and additional purchase options for extra space.

Thunderbolt ports enable data transfer speeds up to 40 Gbps, while USB ports can reach speeds of 10 Gbps.
Ethernet ports allow high-speed internet connectivity, up to 10,000 Mbps, and HDMI ports provide video and audio connections.

Various power management techniques include monitoring battery drain, using sleep mode, and differentiating between warm/cold boots and hibernate states.

A computer performs four primary functions: input (data gathering), processing (manipulation and calculation), output (data display), and storage (data saving).

Computers utilize binary as their language, with bits representing the smallest unit (0 or 1) and bytes consisting of 8 bits; larger units include kilobytes, megabytes, gigabytes, terabytes, and petabytes.