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  Tokens   In C programming language, tokens are the basic building blocks of a program. Tokens can be classified into several categories, and one important category is identifiers.   Identifiers : -Identifiers are names used to identify variables, functions, types, labels, etc.   Rules for identifiers in C:   Must start with a letter (a-z or A-Z) or underscore (_).   Can be followed by letters, digits (0-9), or underscores.   Cannot be a keyword.   Case-sensitive (e.g., "my Variable" and "my variable" are different identifiers).   Keywords : -Keywords are reserved words with predefined meanings in the C language.  Total 32 Keywords in C.    Examples: if, else, for, while, int, char, etc.                                             ...

Structure/Syntax of C program   Syntax: The syntax of a language describes the possible combinations of symbols that form a correct program. Preprocessor Directive: In C programming, a preprocessor directive is a command that instructs the compiler to perform specific actions before the actual compilation of the source code begins. Preprocessor directives start with the '#' symbol and are processed by the preprocessor, a built-in component of the C compiler. They are not part of the C language itself, but they are essential for performing various tasks before the actual code is compiled.  Common preprocessor directives-  #include: Used to include header files into the source code, allowing the program to access functions and declarations defined in those header files.  #define: Used to define constants, macros, or function-like macros for use throughout the program. #ifdef, #ifndef, #else, #endif: Used for conditional compilation, allowing certain c...

  History of C      The history of C programming dates back to the early 1970s when Dennis Ritchie created it at Bell Laboratories. Here's a brief timeline of the major milestones in the history of C:  1969: The development of C began as a successor to the B programming language, which Ken Thompson created. Dennis Ritchie wanted to improve upon B's capabilities and efficiency.  1972: The C programming language was developed primarily to support the development of the Unix operating system. Ken Thompson and Dennis Ritchie rewrote Unix in C, which helped in porting the operating system to different computer architectures easily. 1978: The first edition of "The C Programming Language," also known as the "K&R C," was published. Brian Kernighan and Dennis Ritchie wrote it, becoming the authoritative reference for C programming. 1983: The American National Standards Institute (ANSI) formed a committee to establish a standard for the C language. The ...

 Introduction   C is a general-purpose programming language that was developed in the early 1970s by Dennis Ritchie at Bell Laboratories. It has since become one of the most widely used programming languages and has influenced the development of many other languages, including C++, Java, and C#. C is known for its efficiency, flexibility, and low-level programming capabilities. It is commonly used for system programming, embedded systems, and developing operating systems. C is also a popular choice for developing applications that require high performance, such as game engines and scientific simulations.   Here are some key features and concepts of C programming:   Syntax: C has a relatively simple syntax compared to some other programming languages. It uses a combination of keywords, variables, data types, operators, and control structures to write programs.  Variables and Data Types: You declare variables to store data in C. Various d...

 Computer Generations   Computers have evolved over time through different generations, each marked by significant technological advancements and changes in design and architecture. These generations are often categorized based on the underlying hardware and the key developments that distinguish one Generation from another. Let's explore the main computer generations: First Generation Computers    The First Generation of computers refers to the initial period of electronic computing, characterized by the use of vacuum tubes as the primary electronic component. This Generation spans the 1940s and 1950s and is marked by groundbreaking developments in computer technology.  Examples of First-Generation Computers:  o ENIAC (Electronic Numerical Integrator and Computer): Completed in 1945, ENIAC was one of the first electronic general-purpose computers. It was designed to calculate artillery firing tables for the United States Army during World War ...

INTRODUCTION TO E-MAIL     Electronic mail (E-mail)  is an electronic message transmitted over internet/computer  network from one user to another. E-mail is a text based mail consisting of lines of  text, and can include file attachments. These attachments could be pictures, documents,  spreadsheets, audio files, video files etc.  The key features of e-mail are as follows: • E-mail can be sent to one person or more than one person at the same time. • The recipient of e-mail can open the e-mail at his/her convenience. • Since messages are transmitted electronically over internet, it is a faster way to  communicate with the people. Persons could be located in the same office, home,  building, or anywhere in the world. • E-mail messages can be sent or received at any time and are typically sent over a  network (office network or more likely internet). • If so desired, a copy of the e-mail message that the sender has sent can be saved ...

Spreadsheet Package : A spreadsheet package is an application software that stores data in an organized way and help to  analyse, calculate, compare the data or values. It also enables to present information in graphs, pie charts, histograms, etc. for doing analysis. It is commonly used for generating results, planning budgets, etc.  Some Commonly used spreadsheet packages are MS Excel, Open Office Calc,etc. Features of a Spreadsheet Package: 1. Large Calculations can be done easily and accurately within a short span of time. 2. the data or information can be exported to or imported from other packages. 3. Data or information can be expressed in pictorial form(charts and graphs) 4. The formulae are automatically applied to new data when the value of previous data changes. 5. Large volume of data can be easily organised and manipulated.

Operator : Operator are tokens that does computation(calculation) with designated or given values in expression. Operators when applied on operands form an expression. Operand : Operand is the value or variable on which calculation is performed. Operators are can be classified in three  categorize : 1. Arithmetic Operator : Arithmetic operators are those operators which are used for arithmetic or mathematical calculations. In Python, the arithmetic operators are:   Addition (+) : It is used to sum two operands.  Subtraction (-) : It gives difference between two operands.  Multiplication ( * ) : It gives us product of the two operands.  Division (/) : It gives us Quotient of the two operands. Floor Division ( // ) : It gives us quotient of two  operands(without fractional part). Modules ( % ) : It gives us integer remainder after division of 'a'  by 'b' -(a % b). Exponent ( ** ) : It gives us product of 'a' by itself  'b' times(a to  the power...

Most of the official jobs today are dependent on computers. Computer helps in accomplishing different types of official tasks with the help of 'Office Package'. With the help of 'Office Package ' to accomplish basic tasks like typing and composing letters, doing calculations and comparisons, manipulation data and generating multiple types of reports, making presentation for demonstration, seminars etc.   For example: MS Office, OpenOffice, etc. Office package includes the following applications: 1. Word Processor:  A word processor is a type of application software that enables to create a documents by enabling to type text, insert page number, header, footer, edit, modify , and to take print or save documents in soft copy for future use.   2. Spreadsheet:   A spreadsheet package is an application software that stores data in an organized way and help to  analyse, calculate, compare the data or values. It also enables to present information in graphs, pie c...

  Character Set : Character Set in Python consist of  valid characters such as alphabets, digits or special characters that are recognized by the library of Python Language. Alphabets:                         A,B,......Y,Z or a,b,.......y,z. Digits:                               0,1,2,3,4,5,6,7,8,9 Special Character:      ~!@#$%^&*()_+{}[];:'"\,./<> etc. White spaces    :             Blank space, new line, etc. Token: The smallest individual unit in a program is referred as 'Token'. It is also called Lexical Element or Lexical Unit. It can be categorized as: 1. Keywords : Keywords are the reserved words that has specific function in a program. These words are used while writing program to get desired output. The keywords are executed  as its purp...

The working of a Database starts with creation of tables. There are different elements in database package, all of which work together to make the database package function. Each element has a specific role to play. Some of them:- 1. Field Name: A field name is the identifier of a field as it contains the data that is to be stored in that field. It may consist of letters, numbers and special characters. " It is the name of the column of a table." 2. Field Type: Field type or Data type signifies the type of data which will be entered in a particular field. 3. Properties: Field properties signify the behavior of the field. It helps in keeping the consistency of the data entered by the user. 4. Queries: Queries are the format of requirement of information that can be received on the basis of records stored in a table. 5. Forms: Forms are the layout for the entry of data. They are used as format to let the operatior feed/input data for creating records in a table. 6. Report: Repo...

Database : A database is an organized collection of related information in which facts are properly arranged and stored.  A database is made up of a basic unit called “Table”.  A table is made of different ‘Fields’ and ‘Records’.  Record : Collection of organized data or related facts is called Record.  Field : A field is a collection of same data types.  DBMS (Database Management System): A database Management System is a tool for managing and manipulating information of a database.  The main Functions of a DBMS is:  Creating Database.   Adding Records.  Modifying Records.  Displaying Records.   Storing Records.   Deleting Records.   Generating Reports.   Printing Reports.  Some Example of DBMS: MS Access, My-SQL,etc.  Features of DBMS: DBMS ensures data security. DBMS facilitates the sharing of data among different database. DBMS controls data inconsistency to a large extent. DBMS...

  Now, we are learning how to install python in our computer. 1. For Installing Python on Windows Operating System Connect the internet and then open any browser. visit  https://www.python.org/  and go to download section and choose windows. and Download the installer File(".exe") for 64 bit system download x64 and for 32 bit system x86 in local computer. Launch the Downloaded package by double click on it. "Open File- Security Warning" Dialog Box appears on the screen. Click on Run Option. Now the Python setup window appears. Check the both checkboxes of install launcher for all users and add python(downloaded version)  to Path. Now Click on "Install Now" option. and wait some time for installing. When the installation will completed "setup was successfull" notice we get now click on Close button to Complete installation process.

A set of predefined instructions in logical manner makes up a program.  One of the most important aspects of computer field is to make ‘Programs’.  A program is written in a computer language, like BASIC, ‘C’, ‘C++’, Python, etc.  A computer language consists of codes which are combined in accordance with a predefined syntax, that conveys the instructions to the components (ALU) of CPU. Python has evolved into a very useful language as it is simple and is being used in many fields such as in Robotics, Scientific Purposes (Used by NASA), search Engines (Google), YouTube, Hardware Testing (Being used by Intel, Cisco, HP, etc.), GUI Interface (Popularly used in GIMP), 3D Animation (Maya) etc. Features of Python Programming Language:   The keywords of Python are in simple English. Python library is portable and compatible with all types of Operating System hence it is known as platform independent programming language. Python is an interpreted language i.e. Python interp...

     Super Computer Supercomputers are the fastest computer and have a large data storage capacity. A supercomputer can execute more than 100 million instruction per second. It has multiple processors which are based on parallel processing architecture for achieving high speed. It is made for some special purpose. It can support more than 1000 users at a time. It is used for Space Research, satellite management, Wheatear forecasting Aerodynamics, and complex computation. Ø First Indian Super Computer “PARAM2000”. Ø The first supercomputer is CDC 6600 (designed by CDC Control Data Corporation in USA). Ø The first five fastest supercomputer of the world are 1.       Summit (US) 2.     Sierra (US) ... 3.     Sunway TaihuLight (China) ... 4.     Tianhe-2 (China) ... 5.      Frontera (US) Ø Speed of Supercomputer is measured in FLOPS. Ø FLOPS (Floating Point O...

Binary arithmetic is simpler to learn because binary number system deals with only two digits - 0 and 1. Binary number perform all arithmetic operation such as Addition, Substraction, Multiplication and compliment as in decimal number system. Binary Addition The addition table for binary arithmetic consist of only the following four entries: 0+0=0 0+1=1 1+0=1 1+1=0 , plus a carry of 1 to the next column.     1011        + 1100    10111     1100    + 1100     11000 Binary Substraction There are three ways to do substraction between binary numbers:- 1. Simple Substraction 2. Substraction using 1's Complement 3. Substraction using 2's Complement Simple Substraction: The complete table of binary substraction is as follows: 0-0=0 0-1=1, borrow 1 from next column 1-0=1 1-1=0    1101 - 0101   1000     1001   - 0111    0...