Lecture 1 - Intro Flashcards
What is a program?
A composition/collection of instructions/directions prepared by a programmer that is meant to control some computer as that computer performs the task intended by the programmer (sometimes also referred to as software but some programs are stored within unchangeable hardware). They can be small (a few lines of code) or very large (tens of millions of lines of code).
What is a programmer?
Someone who can design, create, and test computer programs (also known as a software developer or a coder).
What is a computer?
A device that:
– Accepts input (e.g., keyboard, mouse, touch screen, network interface, sensor)
– Processes data
– Stores data (usually in some form of memory)
– Retrieves data
– Produces output (e.g., printed, display, actuator, network interface)
What are some types of computers?
- Personal or microcomputers (Desktops, Notebooks, Laptops)
- Handheld (smartphones, PDAs)
- Mainframes
- Supercomputers
- Cloud computing environments (Amazon ECS, Microsoft Azure, Google Cloud Platform)
What is Hardware?
The physical devices that make up a computer. A computer is itself a system composed of several physical components that all work together.
What are the typical major components of a computer?
Central processing unit (CPU)
Main memory
Secondary storage devices
Input and output devices
How are the components of a computer connected?
electrically, using multiple wires known as a bus
What is a Central Processing Unit (CPU)?
The beating heart of a computer. This is the part that actually executes the programs instructions. Therefore it is the most important component – without it, the computer is not a general-purpose computer (i.e., cannot run general programs).
CPUs used to be very, very large in physical size. CPU speed sometimes measured in Millions of Instructions per Seconds (MIPS).
What is a Microprocessor?
This is a CPU designed and manufactured to fit onto a single integrated circuit (IC).
If the CPU is on an IC that also has a bit of main memory, the result is often called a microcontroller.
What is main memory?
Where the computer stores a program while the program is running and where data used by the program is also stored just before and just after it is processed. Normally known as random access memory (RAM).
Computer is designed to allow CPU quick access to RAM (i.e., reading and writing RAM).
Why is RAM only suitable for temporary storage?
Part of RAM’s design makes it volatile, hence it is only suitable for temporary storage which means the contents of RAM are erased when the computer is powered off!
What are secondary storage devices?
Meant to hold programs and data for long periods of time (days, months, years). This is the usual place we keep programs!
What are some types of secondary storage devices?
Hard drive (disk drive): magnetically encodes data onto a spinning circular disk.
Solid state drive (SSD): no moving parts, stores data in solid state memory.
Flash memory: portable, no physical disk (e.g., USB memory stick).
Optical devices: data encoded via lasers onto special reflective surfaces.
Network Attached Storage (NAS): actual storage device kept somewhere else, but we can send/receive data and programs over a network connection.
What is input?
data that is collected by the computer from people or from other devices or both
What are input devices?
Hardware component that collects/gathers the data (e.g., keyboard, mouse, touchscreen, scanner, camera, game controller, network card, wi-fi port).
Disk drives can be considered input devices (i.e., we use them to load programs and data into main memory).
