Chapter 1: Introduction to Computers, Programs, and Java Flashcards
Computer Bus
A structure which transmits data between different components of the same computer or between two different computers.
A computer bus consist…
- Storage Devices (disk, CD, and Tape)
- Memory
- CPU
- Communication Devices(Modem, and NIC)
- Input Devices(Keyboards, mouse, etc.)
- Output Devices(Monitor, Printer, etc.,)
What is the CPU?
The CPU can be thought of as the brain of the computer. It retrieves instructions from memory and executes them.
How is CPU speed measured?
The CPU speed, known more specifically as clock speed, is measured in hertz’s. One hertz is equal to one cycle/pulse per second, with most modern day computers being measured in gigahertz (which is 1,000,000,000 Hz) 🤯. Intel’s newest processors operate at 3 GHz 🤯🤯🤯🤯.
What is memory?
Memory is to store data and program instructions for the CPU to execute. Measured in bytes (8 bits), a memory byte is never empty but it’s contents may be meaningless to your program.
A memory unit is…
An ordered sequence of bytes.
A program must be brought where before it can be executed?
A program must be brought to memory before it can be executed.
What are programs called when readable to humans?
Source Code
What is a computer bit?
A computer bit is the smallest increment of data on a computer. Composing only of 0 or 1. This is what is known as binary or machine code. 8 bits = one byte.
Why do computers only use zero’s and one’s?
Because computers only have two stable states, and conventionally we call these states 1 or 0.
How is a byte different from a bit?
A byte is the minimum storage unit whereas a bit is a single stable state of the computer called 1 or 0 by convention.
How many bits in a byte?
8
What are the three main types of storage devices?
- Disk Drives(hard disk)
- CD Drives (CD-R and CD-RW)
- USB flash Drives
Why do we have storage devices?
Because memory is volitile and information is lost when the power is off. Therefore programs and data are permanently stored on storage devices and are moved to memory when the computer actually uses them.
What does a monitor do?
The monitor displays information (text and graphics).
What determines the quality of display of a monitor?
Resolution and dot pitch(the distance between dots on a display screen).
What is a “dot”?
Dot’s are the smallest, identifiable, part of an image. Measure commonly in what is known as DPI “Dots Per Inch”. Monitors display images as array’s of dots.
What is dot pitch?
The dot pitch is the amount of space between pixels, measured in millimeters. The smaller the dot pitch, the sharper the display.
What is resolution?
The screen resolution specifices the number of pixels in horizontal and vertical dimensions of the display device.
What tool is used to translate source code into machine code?
Interpreter or a compiler.
What is the fundamental difference between an interpreter and a compiler?
An interpreter is a source code translating tool which translates the source code line by line and directly executes each line. A compiler on the other hand, translates your source all at once, into machine code, and makes a machine code file that is then translated all at once.
Define operating system.
An operating system is a program that manages and controls a computer’s activites.
Why Java?
Java is a general purpose language and is the internet programming language.
What are some of the applications of Java?
- Develop standalone applications (software that doesn’t require the internet to run)
- Develop browser applications
- Develop applications for hand-held devices
- Develop applications for web servers.
What is a web server?
A web server is the computer software and hardware that accepts HTTP and HTTPS request and gives HTTP and HTTPS responses.
Java is like what other language but simpler and with less negative aspects?
C++
What is a programming paradigm?
programming paradigms are ways of classifying programming languages based on their features.
A regular modem and DSL are similar in what way and different in what way?
A regular modem uses phone lines to transfer data at 56,000 bits per second. DSL also uses phone lines but transfer speeds are 20x faster than that of a regular modem.
How is a cable modem similar to DSL?
A cable modem uses the TV cable line maintained by the cable company and its transfer speeds are as fast as DSL.
The NIC(network interface card) connects the computer to…
LAN(local area network)
A high speed NIC is also known as…
1000BaseT. Can transfer data at 1000 mbps(1 million bits per second)
NIC, Modems, DSL, are all examples of…
Communication Devices
A computer program is also known as _____(1)____ and it is instructions to the computer.
Software
Machine Language is…
a set of primitive instructions built into every computer. The instructions are in the form of binary code.
Assembly languages are “in between” what two levels of programming language?
Machine Language and High-level language
What program converts assembly language into machine code?
Assembler
High level languages are described as…
Enligh-like and easy to learn and program.
A program written in a high-level language is called a…
source program/ source code
High level languages are translated into machine code via ___1___ or ___2____?
- Interpreter
- Compiler
What is a Java class file?
A Java class file is a file containing java bytecode that can be executed on Java virtual machine.
Users and applications communicate/access with a computers hardware via…
Operating systems
The most important code running on a computer is…
The operating system.
What are the major responsobilities of an operating system?
- Controlling and monitoring system activities
- Allocating and assigning system resources
- scheduling operations
JDK stands for…
Java Developer Toolkit; contains several separate programs for compiling, running, and testing Java programs.
Opening and closing parentheses are used with…
Methods
Opening and closing brackets are used with…
Arrays
Opening and closing braces are used for…
Denote a block to enclose statements.
