SOME BASIC KEYWORDS IN TECH. FIELD
WEB BROWSERS :
1.The web browser is an application that provides access to the webserver, sends a network request to URL, obtain resources, and interactively represent them or in other term we also say this A web browser is application software for accessing the World Wide Web .
2.Now the point is what is World Wide Web — The World Wide Web (WWW), commonly known as the Web, is an information system where documents and other web resorces are identified by URLs, such as https://medium.com/or via ip address(8.8.8.8).
3. some modern web browser-
- Firefox — Gecko Software
- Safari — WebKit
- Chrome, Opera — Blink
- Internet Explorer — Trident
4. A web browser is not the same as search engine , A search engine is a website that provides links to other websites. However, to connect to a website’s server and display its web pages, a user must have a web browser installed.
5.A web browser retrieves information from different parts of the internet and displays it on desktop or mobile devices. The information is transferred using the Hypertext Transfer Protocol also called Http , which defines how text and media files are transmitted on the web.
When a browser fetches data from the internet server, it uses a software tool called rendering engine which translate the data written in Hypertext Markup Language (HTML) into readable format, i.e, text, images and render it on the user interface of the browser.
WEB CRAWLERS :
Web crawler is a program that acts as an automated script which browses through the internet pages datas in a systematic way.Crawlers would also help in validating HTML codes and checking links as google, yandex bots etc.Crawlers would also help in validating HTML codes and checking links as google, yandex bots etc.The web crawler follows all the hyperlinks in the websites and visits other websites as well. Each page is a new data for web crawl.
USED CASE — it’s very difficult to crawl millions of pages, specific rules and priorities are followed according to the requirements of the company and clients like the Relative importance of any webpage, Number of visits, Type of content like blogs, posts, user profile, etc.Google uses special search algorithms named page algorithm — it gives each page a relative score of importance and authority by evaluating the quality and quantity of its links.
By using some framework we can create our own crawler like — SCRAPY , SELENIUM , APACHE NUTCH ..many more
PROGRAMMING LANGUAGES:
1.Before knowing is what is programming language? we have to first understand what is programming ?
Programming is a way for us to give instructions to computer .whatever we do anything on our system or computer from moving cursor to watching moving , playing games etc behind the scene everything done by some program or we can say code.
computer can understand binary that means 0’s or 1’s . so just imagine having to learn and how to communicate in binary. it would be so hard to understand and grasp . That’s why we have programming languages.There are two types of language — high level and low level .High-level languages are languages such as Java, Python, JavaScript, and C#. These languages are closer to the English language and easy for humans to learn and understand. An example of a low-level language is Assembly, which is closer to machine code.
we write code in high level language and convert that language into low level language using compiler or assembler.
2.According to Wikipedia, There are almost 700 programming languages in existence but only a dozen of them are popular and of significant importance.
Types of programming languages (high level)-
- Procedural Language
- Specifies a series of well-structured steps and procedures to compose a
program.
- Contains a systematic order of statements functions and commands to
complete a task. - Functional Language
- Writing a program only in pure functions i.e., never modify variables but
only create new ones as an output.
- Used in a situation where we have to perform lots of different
operations on the same set of data like ML. - object oriented language-
- An object-oriented language is a computer programming language that. revolves around the concept of an object. Object-oriented languages were developed to make it easier to develop, debug, reuse, and maintain software than is possible with earlier languages.
- code+data=objects.
“one programming language can be of all 3 types like — Python”
Some example of programming languages are — Java , python , scala ,R , golang , html, css, dart, kotlin ,c++, swift , c , c# , ruby etc
DATABASE VS DATABASE SYSTEM :
1.Data:
Representation of facts, concepts, or instructions in a formalized manner that should be suitable for communication, interpretation, or processing by a human or electronic machine.
Database:
Database is an organized collection of interrelated data stored in a computer.
Importance :
• It gives us a highly efficient method for handling a large number of different types of data with ease.
- It allows large amount of data to be stored systematically and these data to be easily retrieved, filtered, sorted and updated efficiently and accurately.
- Represents some aspects of the real world.
- A database is a logically coherent collection of data with some inherent meaning.
- A database is designed, built, and populated with data for a specific purpose.
Database system
A database management system (DBMS) is a software used for manipulating (storing, querying) a collection of logically related data (database).
properties:
- Data redundancy and inconsistency — multiple file-formats, duplication of information in different files.
- Difficulty in accessing data — need to re-write programs to carry out new tasks.
- Data isolation
- Integrity problems — hard to add or change constraints.
- Atomicity of updates — failures may leave the database in an inconsistent state with partial updates carried out.
- Concurrent access from multiple users.
- Solve security problems.
A DBMS together with a database form the database system.
Applications of DBMS
- Banking- All transactions
- Airlines- Reservations, schedules
- Universities- Registrations, result etc.