Computer Science
Computer science is based on an efficient way of Learning & Designing Algorithms, Learning Programming Fundamentals as well as Basic programming languages like C, C++, Python, Java, HTML, CSS, JavaScript, MySQL, etc. Sciencerack is the best site that is completely focused on Computer Science & APK Apps For Android, iOS & PC.
Computer Science is based on the study of computers and computing systems. Computer scientists completely work differently than electrical and computer engineers. They mostly interact with software and software systems including theory, design, development, and application.
What is a Computer?
A computer is a programmable electronic device that evaluates data according to a set of commands, produce output as a result and store it for future use. A computer is controlled by programmed instructions. It performs four general operations i.e input, processing, output, and storage.
What is Computer Science?
Computer Science deals with the study of how data is processed and digitized automatically. We can say it as a process of searching for the digitalized solution to real-world issues & problems
What is the APK?
APK stands for Android Package Kit. It is a complete package file format used by the Android operating system for the purpose to distribute and install mobile apps similar to Windows (PC) systems that use a .exe file for software installation. the APK works in the same manner for Android.
When you try to download an APK online, it generally means that you’re downloading an app like KineMaster Pro. Many android users grab apps from the Google Play Store, as they don’t have enough knowledge about the word APK. But most of the time it’s very necessary for you to do otherwise.
What Are APK Apps/ Files?
APK file is an advanced way to access new and exciting features of the android, iOS & PC apps. Users can download and enjoy apps that are restricted or not available for free. Some of the important APK Apps for android users are as follows:
Download Top APK Apps For Android, iOS (iPhone & iPad) & PC
Computer Science
Computer science is the study of computing, programming, and computation in association with computer systems. This study involves theories that define how a computer works to design, test, and analyze concepts. Computer science mainly lies in the mathematical foundation than a scientific one.
HealthCare Naturally
We are living in the world of Artificial intelligence. Machines are present everywhere and in every industry. This will cause an increase in different kinds of pollution resulting in a decrease in the overall life span of human beings.
As various kinds of diseases are spreading all around the globe. Similarly, drugs and methods to cure these diseases are improving day by day. Three methods are most popular to fight these diseases.
- Allopathy
- Homeopathy/Natural Method
- Surgery
Both Alelophty and surgery are very expensive and very dangerous for health. But homeopathy is the best method to fight these diseases. It’s based on natural ingredients and doesn’t have any side effects on human health.
Here I am going to discuss some Natural Method to cure some common diseases:
Categories Of Computer
A computer is a fundamental unit of computer science. There are two major categories of computer Digital computers and Analog computers. Digital computer functions by receiving & computing data converted in binary form (0 and 1) while Analog computer functions continuously, no matter what the variations are in the input i.e temperature, current.
Analog Computer
An Analog computer is a type of computer which functions continuously, no matter what the variations are in the input. These variations may include instability in current, temperature, electric, and mechanical parts. The best examples of an analog computer are Oscilloscopes, thermostats, and thermometer.
Digital Computer
The digital computer is a type of computer which receives and computes the data converted in binary form. It is most commonly used in all fields of life. Generally, it is an electronic device. The digital computer gets input and functions in a discrete manner.
Hybrid Computer
Hybrid computers are used for special purpose & combine the characteristics of both analog and digital computers. Basically, they are digital computer which receives analog signals and transforms them into digital signals. Hybrid computers generally used for scientific applications such as airplanes and hospitals.
Some major examples are:
- Electrocardiogram Machines
- Ultrasound Machines
- Monitoring Machines
Types of Analog Computer
Following are the important types of analog computers:
Slide Rules
One of the only and maximum recognizable mechanical analog computer systems is the slide rule, a tool for approximating primary mathematical calculations. Users slide a hashed rod to line up with diverse markings on some other rod and study the tool primarily based totally on the lineup of diverse hash marks.
Differential Analyzers
Another well-known mechanical analog pc, the differential analyzer, became capable of resolve differential equations. With designs as antique because of the early 1800s, the differential analyzer became subtle withinside the 1930s, and noticed use via the mid 20th century.
The machines have been huge in the evaluation of trendy computer systems, filling a table-sized space.
The Castle Clock
The Castle clock is a great illustration of the diverse makes use of mechanical analog computer systems. Al-Jarazi invented this well-known pc, which became able to saving programming instructions. The 11-foot excessive tool displayed the time, the zodiac, and the orbits of the solar and moon.
The computational part of the tool allowed customers to set the variable period of the day primarily based totally on the modern season. Described in 1206, the pc incomputer science became very complicated for its period.
Electronic Analog Computers
Modern analog computer systems use electric alerts flowing via diverse resistors and capacitors to simulate bodily phenomena, as opposed to the mechanical interplay of components. The voltage of the sign offers pertinent readouts or displays.
Electronic analog computer systems noticed extensive use in computing and army era in the course of the center part of the 20th century, in such capacities as missile and plane testing.
Types of Digital Computer
The digital computer systems which can be to be had in recent times range of their sizes and types. These digital computer systems are extensively labeled into 4 classes primarily based totally on their length and type.
(i) Micro Computers
Microcomputers are small low forged and unmarried-consumer virtual computer systems. It is a tool with a microprocessor, enter the unit, garage unit, and CPU(Central Processing Unit).
Microcomputer computers previously a typically used time period for Personal Computers, in particular, any of the elegance of any small virtual computer systems. Its CPU contained on a single incorporated semiconductor chip.
IBM PC primarily based totally on Pentium microprocessors and Apple Macintosh are a few examples of microcomputers. Types of Microcomputers encompass laptop computer systems, pocketbook computer systems or laptops, pill computing, handheld computer, smartphones, and pocketbook.
(ii) Mainframe Computers
Mainframe computer systems are commonly huge length computer systems particularly used for storing huge quantities of facts and processing. It is understood for an excessive degree of reliability.
These machines are utilized by a business enterprise that calls for essential software inclusive of the census, purchaser information for huge calculation which calls for an excessive extent of fact processing.
(iii) Mini Computers
These carry out multi-tasking and permit terminals to be related to their services. the capacity to attach minicomputers to every different and mainframe has popularized them amongst large businesses.
This use is being challenged with the aid of using the improvement withinside the microcomputer variety and the exercise of beginning sources of microcomputer below a network. Minicomputers remain identified as being capable of method huge quantities of facts.
(iv) Super Computers
Supercomputers are very costly and the world’s quickest computer systems to be had. These computer systems have heaps of processors that carry out trillions of calculations per second and consequently, the quickest recognized ever.
Supercomputers are used drastically in businesses and companies that require huge calculations.
Analog Vs Digital Computer
The main difference between analog and digital computers is the way they process data. Analog computer functions continuously. Examples: Oscilloscopes & thermometer. While the digital computer gets Input which may consist of letters, digits represented in binary ( 0 & 1) form. Examples: personal & supercomputer.
Components of Computer
The computer is a combination of two main components i.e software & hardware. Software is the logical part of a computer that cannot be touched or replaced. And hardware is the physical part of computers that can be touched and replaced.
(i) Software
Software is a set of computer instructions that directs a computer, how to interacts with the user, and to process the user’s data. It includes libraries, programs, and non-executable data, that directs all the peripheral devices on the entire computer system, what exactly to do, and how to perform.
Types of Software
In computer science, the software is nothing but a set of programs and data that enables the hardware to do something useful. Without software, computers would be useless. System Software and Application Software are two major types of software.
(a) System Software
The system software is general-purpose software. It manages and controls all operations of the computer system. It also manages the usage and allocation of different hardware resources. In addition, the system software allows other application programs to run and execute properly. Types of System software are:
- Operating systems
- Device drivers
- Middleware
- Utility software
- Shells and windowing systems
(b) Application Software
Application software is almost designed to perform some specific task. The task is according to the requirement of the user. We use different types of application software packages on our computer like a word processor, spreadsheet, & database design in our daily life.
- Word Processors
- Graphics Software
- Database Software
- Spreadsheet Software
- Presentation Software
- Web Browsers
- Enterprise Software
- Information Worker Software
- Multimedia Software
- Education & Reference Software
- Content Access Software
(ii) Hardware
Internal Hardware Components
- Motherboard,
- Central Processing Unit (CPU)
- Random Access Memory (RAM)
- Hard Drive
- Optical Drive
- Heat Sink
- Power Supply
- Transistors
- Chips
- A Graphics Processing Unit (GPU)
- Network Interface Card (NIC)
- Universal Serial Bus (USB) Ports.
External Hardware Components
- Pointing Devices
- Keyboard
- Microphone,
- Camera
- Scanner
- USB Flash Drive
- Memory card
- Monitors
- Printers
- Speakers
- Headphones
- Earphones/Earbuds
Difference B/w Software Vs Hardware
There is a great difference between software and hardware. Both are completely different components of a computer system.
Software is a set of computer instructions that directs a computer, how to interacts with the user, and to process the user’s data. While Hardware is the physical part of a computer that bodily additives a pc machine calls for to function.
Categories of Computer Devices
Computer devices in computer science are normally categorized into Four major types i.e Input Devices, Processing Devices, Output Devices & Storage Devices.
Peripheral Devices
Peripheral devices are those devices through which data can be entered into or retrieved from the system. On the other hand, they are those components that can be connected to the system unit internally or externally. It comprises the input and output devices. Typical examples are:
Peripheral devices For Input
- Keyboard
- Computer mouse
- Graphic tablet
- Touchscreen
- Barcode reader
- Image scanner
- Microphone
- Webcam
- Game controller
- Light pen
- Scanner
- Digital camera
Peripheral devices For Output
- Computer display
- Printer
- Projector
- Speaker
Peripheral devices For Storage
- Floppy disk drive
- Flash drive
- Disk drive
- Smartphone or Tablet computer storage interface
- CD/DVD drive
Peripheral Devices For Both Input/Output
- Modem
- Network interface controller (NIC)
Input Devices
An input device is a hardware component that is used to send data to a computer for the purpose to process it. Most input devices are either used to interact with or control the computer. The most used input devices are the mouse and the keyboard, but there exists a huge number of other input devices in the field of computer science.
Examples are:
- Keyboard
- Mouse
- Microphone
- Digital Camera
- Scanner
- Touchscreen
- Barcode Reader
- Webcam
- Biometric devices
- Stylus
- Joy Stick
- Light pen
- Track Ball
- Graphic Tablet
- Magnetic Ink Card Reader(MICR)
- Optical Character Reader(OCR)
- Bar Code Reader
- Optical Mark Reader(OMR)
Output Devices
An output device is a hardware component used to display, project, or physically demonstrate the results of data processed by a computer in audio or video format. The most common output devices are monitors, projectors (video), headphones, speakers (audio), printers, and plotters.
Examples are:
- Monitor
- Printer
- Headphones
- Computer Speakers
- Projector
- GPS
- Sound card
- Video card
- Braille reader
- Speech – Generating device
- Plotter
Difference B/w Input Devices Vs Output Devices
The major difference between an input device and an output device is that the input devices are used to sends data to the computer, whereas the output devices are used to receives data from the computer. There are many other devices that are used to provide computers with additional functionality are known as peripheral devices.
Processing Devices
A processing device is any device in a computer that used to process the data, using instructions from the program. The major function of processing devices is to manage & do a variety of calculations as well as monitor the hardware tools.
CPU is an essential processing device in a computer system. It’s not wrong to say that it’s the brain of a computer. The function of the CPU is to recognizes and executes all input/output instructions & perform numerical or logical comparisons as well.
Examples are:
- Central Processing Unit (CPU)
- Graphics Processing Unit (GPU)
- Motherboard
- Random-Access Memory (RAM)
- Read-Only Memory (ROM)
- Network Card
- Sound Card
- Video Card
- Clock
- Chipset
- Data Bus
- Address Bus
Storage Devices
A storage device known as storage medium or storage media is a computer hardware component used for saving, carrying, and retrieving processed or unprocessed data as and when required. These devices are used to store and retain information short-term or long-term.
A storage device is one of the fundamental parts of the computer system in the field of computer science. The purpose of these devices is generally to store all data and applications in a computer except for hardware firmware. These are available in different shapes and sizes depending on the needs and functionalities.
Examples are:
- Floppy Diskette
- Hard Drive
- Zip Diskette
- Blu-Ray Disc
- CD-ROM Disc
- Memory Card
- USB Flash Drive
- Cloud Storage
- Network Media
- OMR
- Punch Card
Types of Storage Devices
- Magnetic Storage Device
- Optical Storage Device
- Flash Memory Device
- Online and Cloud
- Paper Storage
Communication Devices
Communication devices are connected together for the purpose of sharing data or resources within a network. Common communication devices are:
- Network interface card (NIC)
- Modem
- Hubs
- Bridges
- Repeaters
- Routers
- Gateway
- Switches
What is a Computer Network?
A computer network is a collection of inter-connected computers for sharing information and various resources. Through a computer network, you can share information, resources as well as communicate in a fast and flexible way. Common Types of Computer Networks are:
- LAN (Local Area Network)
- MAN (Metropolitan Area Network)
- WAN (Wide Area Network)
Network Topology
A network topology is a physical layout of a computer network through which computes, cables, and other components are connected with each other for data communication. Important types of network topologies are:
- Bus Topology
- Star Topology
- Ring Topology
- Mesh Topology
- Tree Topology
- Hybrid Topology
Communication Channels In Networks
Communication Channels are also called communication media or transmission media. A communication channel is a physical path that connects the sender and receiver for the transmission of data & information over a network. The communication channels are divided into two major types:
- Guided Media
- Un-Guided Media
Guided Media
Guided Media is also known as wired or bounded media as data signals are enclosed in a cabling media. In guided media communication devices are directly connected to each other via wires or physical media for data transmission. Examples are:
- Twisted Pair Cables
- Coaxial Cables
- Fiber Optics Cables
Un-Guided Media
Un-Guided Media is also known as wireless media. It can be used at each and every place but it’s impossible to install cables. Data communication can be done via electromagnetic waves of different frequencies. Common examples are:
- Microwave
- Radio Wave
- Cellular
- Infrared
- Satellite
Network Protocols
A Network Protocol is simply some special set of rules uses in digital communication to ensure the systematic and safe transfer of data our a network. They are also used by nodes on the network when they communicate. Without proper protocols, no effective communication can take place.
They are used everywhere from sending an e-mail to visiting websites. Everything you send and receive from the internetwork according to these protocols. These protocols exist in several layers of the OSI Model. Here are some important protocols used in common communications.
- Transmission Control Protocol/ Internet Protocol (TCP/IP)
- User Datagram Protocol (UDP)
- Point to Point Protocol (PPP)
- Voice Over Internet Protocol (VoIP)
- Simple Mail Transfer Protocols (SMTP)
- Post Office Protocol (POP3)
- Internet Message Access Protocol (IMAP)
- HyperText Transfer Protocol (HTTP)
- HyperText Transfer Protocol Secure (HTTPS)
- File Transfer Protocol (FTP)
- Remote Login
- Telnet
Data Transmission Mode
Data transmission modes are an important part of networking and play an important role in the field of computer science. Transmission mode means the pattern or method used for transferring data between two devices. It is also known as the communication mode. Busses are used to design networks to allow communication to occur between individual devices that are interconnected.
There are three types of data transmission mode:
- Simplex
- Half-Duplex
- Full-Duplex
OSI Model
OSI stands for Open System Interconnection. An open system is a model that allows any two systems to communicate even if their architectures are different. OSI is a supermodel for communication between different computers. It is a complete model that covers all aspects of network communications.
Layers of the OSI Model
OSI model consists of seven layers. Each layer in this model performs a specific function in network communication. OSI model is also called Reference Model because it presents an idea rather than reality. No communication protocol follows this model by 100%.
- Application Layer
- Presentation Layer
- Session Layer
- Transport Layer
- Network Layer
- Data Link Layer
- Physical Layer