INTERNET USE

1. Network and internet

Now think about city streets - they're hard to navigate. Same with a computer network. It's like the same confusing street system, but the more you wander, the simpler it seems: every street is a data path, and every house in the system is a computer or other device connecting to the network. When you send an email to a friend or share a photo on a social network (such as Facebook or Instragram), your information travels along these virtual 'streets' to the right 'home', i.e. the recipient's device. Just like in the real world, on a computer, you can choose your neighbours or the people you interact with by creating several networks, such as a local area network (LAN), which is just your home internet network, with only the devices in your home connected to it, e.g. computers, smartphones, televisions, and limited to sharing information only between the people living in your home.
However, you often get tired of communicating only with your own people and want to know more and hear something new. That's when we connect to the World Wide Area Network (WAN), which allows us to extend the boundaries of communication created by our local network and connect to a much larger world. Let's go back to the street system and imagine that it is a highway that connects our city to many different towns or even countries and allows different information to travel beyond the walls of our homes.
These networks - our streets and motorways - eventually merge into one huge network called the Internet. It allows us to communicate, share and find information from any corner of the world. Just think, with the push of a button you can be anywhere in the world instantly. This is called the power of the internet. In this section, find out how groups of computers are connected by cables or other devices for transmitting information into a common network, and find out what services the internet provides.

1.1. What is a computer network?

A computer network is a group of computers that are connected by cables or other devices for transmitting information.

All modern computers have special network connectors (network boards) which are connected together by special wires and appropriate lugs. For larger networks, network switches are used. For wireless networks, wireless cards are used.

The following types of computer networks are distinguished according to the means of communication organisation and working principles :

• Local Area Network (LAN)
• Wide Area Network (WAN).

A local area network is a computer network that usually connects computers and peripherals in a single office or department, which are located in a limited area, either in a single building or in nearby buildings.

Such a network enables the sharing of common resources:

• media
• printers
• processors
• shared documents and applications for group work

A wide area network is an aggregation of local networks, usually located in a specific area. These networks are connected by various lines of communication to form a single network, regardless of the distance between them, for example: the VIKT network of computers in public institutions or the LITNET network of academic and educational institutions.

1.2. Internet, Intranet, Extranet

The Internet is the world's computer networking system, which allows you to use a computer to search for information and communicate directly with anyone on that network.
An intranet is a smaller, closed (e.g. in the sense of an organisation) version of the Internet that is accessible only by registered users of the intranet.
An extranet is a version of an intranet where the internal network of the institution can be accessed by registered external users.

1.3. Protocols and addresses, Internet services

Protocols and addresses

TCP/IP (Transmission Control Protocol/Internet Protocol). Different protocols control different Internet processes.

Protocols are agreements that allow different computers to exchange information, e.g. FTP, HTTP, SMTP, POP, DNS protocols.

Each computer that connects to a network or the Internet has its own unique IP address, which is represented by a symbolic name, e.g. 193.219.33.31 and 193.219.66.161 are the IP addresses of the computers, and the corresponding symbolic names are www.testuok.lt and www.ecdl.lt

Symbolic names are translated into numeric IP addresses by Domain Name Servers (DNS)

The World Wide Web relies mainly on hypertext - the HTTP protocol and HTML.

Network card settings when connecting to the Internet: 1 - network card; 2 - TCP/IP protocol; 3 - host IP address

Internet services

Web servers provide a variety of services, the most popular of which are:

• Web (WWW or Web)
• e-mail and conferencing (UseNet)
• Internet chat (IRC, Skype)
• file transfer (FTP) and file searching (Gopher)
• connecting to a remote computer (Telnet)

To connect to these servers, the appropriate information transfer protocols are used: http, ftp, gopher, telnet, etc.

1.4. Self-assessment test

Answer the test questions and see if you've learnt what the internet is, what a global and local computer network is, etc.

2. The web. Browser. Google search engine

You already know that the web is one of the services provided by the internet that is very widely used these days. A browser is a program used to display web pages (web pages) on a website, on a company's internal networks or on your own computer. Viewing web pages, often using hypertext links that connect them, is called browsing. When we need information, we can find it very quickly using the web and the Google search engine.

2.1. The web. Hypertext. URL

The World Wide Web (WWW) is a part of the Internet, a collection of resources that can be accessed on the Internet using URLs (Uniform Resource Identifiers, such as https://www.google.com/) linked together by hypertext.
A URL (Uniform Resource Locator) is the universal address of an object (file, web page, computer).

URL structure

Hypertext is text that contains links to other parts of the same document and to other documents stored on the same or any web-based computer. Such links are called hyperlinks
Web clients and servers communicate using the HyperText Transfer Protocol (HTTP), and web documents themselves are created using the standard HyperText Markup Language (HTML).

2.2. Browsers. Search engines. Google search engine

The site's resources can be used in an application called a browser.
A browser is a program used to display web pages (web pages) on a website on your computer. Viewing web pages, often using hypertext links that connect them, is called browsing. In addition to HTML-based documents, browsers can usually display other types of documents.
The most popular browsers are Chrome, Mozilla Firefox, Opera, Edge, Safari, etc.

Most popular web browsers

Search engines

A search engine is a website about other websites and the information they contain

There are many search engines around the world, such as Google, Bing, Yahoo! Search, Bing, Google Search, AltaVista, etc.

If you enter the text you are looking for in the input field of a search engine, it will be searched for in the databases and a list of websites where the text you are looking for is found will be displayed in the browser window.

Google search engine

GOOGLE is the most popular and probably well-known search engine. It is one of the best search engines in the world and is also one of Google's most popular products. The technology giant is constantly evolving and striving to improve its algorithm in order to provide the best results for the end user. "Google uses the most sophisticated algorithms to deliver more accurate results to users.

Google search window

Benefits:

• Additional features include Google Maps, Google Books and Google Scholar;
• Integration with other Google accounts - Youtube, Analytics, Gmail, etc.

Disadvantages:

• Sells data to third parties;
• Takes data from emails and uses it to display ads.

2.3. Downloading and saving information

Once you've found the right information, you can download and save it. You can download different types of files from the web, such as documents, images, videos, apps, extensions and browser toolbars. Once downloaded, you can open, save, play on your computer and cancel. More than 88% of internet users use Google search. However, searching for information, even on the world's most convenient search engine, requires skills and specific knowledge, which you will learn about in this subsection.

How do I download a file and save it on my computer?

If you want to save a file or image on your computer or device, download it.

Assignment. Try this on your computer.

How do I copy and paste text from a web page into a document?

To copy the text of an open document from a browser window into a word processor (e.g. Wordpad) document:

Assignment. Try this on your computer.

How do I copy a URL (web page address) into a document?

To copy a URL from an open web page into a pen document:

Assignment. Try this on your computer.

How do I save an image from a web page to my hard drive?

To save an image from an open web page to your hard drive:

• Hover your mouse over the selected image on the opened web page (the mouse image will change to resemble a hand);
• right-click (a context menu appears);
• select the Save Picture As... command from the context menu;
• in the Save Picture dialog box that appears, specify the folder where the picture will be saved (Save In) and the name of the picture (File name);
• click the Save button.

How do I copy a picture from a web page to a document?

To copy an image from an open web page to an open word processor document:

Assignment. Try this on your computer.

How do I save a web page to a specified disk location?

To save an open web page to your hard drive:

Click More Tools in the top right to save the page as.

In the File Name field of the dialog box that opens, specify the name of the web page to be saved and click the Save button.

3. Receiving, drafting, sending and processing e-mails

Email is one of the most widely used internet services. An email is understood as a letter sent by e-mail. To receive and send e-mails, we must have our own e-mail account, know the recipient's address, have an e-mail program or a web browser, and have a computer connected to an Internet network. See how the email system works in this subsection.

3.1. Advantages and disadvantages of email

Benefits of email

• You can have many email addresses.
• The main advantage of email is the speed of sending/receiving mail. The recipient receives the email within minutes anywhere in the world.
• The cost of sending a letter is much lower than sending a letter by conventional mail.
• You can access your email inbox from anywhere in the world (home, work, travel).
• You can attach any file - document, photo, drawing - to your email

Disadvantages of email

• Spam. If you use the internet regularly and register on some websites, there is a chance that your email address will be taken over by spammers, who will send you millions of spam emails. Avoid registering on obscure websites and block emails from these senders
• Think before you send an email - an email is sent instantly and cannot be recovered. Read the email again before you send it to make sure you won't regret sending it the next day. Don't write anything in an email that you don't want to make public. You never know who the email will go to.

3.2. Structure, types and differences of an email address

'Email address' means the address to which an email subscriber (recipient of electronic services) is registered. It consists of two parts separated by the @ (eta) sign

On the left-hand side, the subscriber's mailbox name. There is no requirement that this name be the actual name of the recipient or the name of an institution. It may be any combination of words or characters chosen by the recipient, or a random code optionally provided by the user during registration

On the right-hand side of the mark, the name of the Postal Service computer (mail server) on which the recipient's mailbox is registered Examples: mokykla@itmc.lt, labas.rytas@ecdl.lt

Types and differences of e-mail

Client mail can only be accessed from your own computer, while web mail is accessible from any computer in the world with an internet connection.

3.3. Email account

When registering, an email account is created on the computer (server) of the postal service provider. Using the details of the account (registration name, password), the subscriber can send and receive e-mails
The easiest way is to use webmail. You do not need to set up a mail account on your computer. You can log in to your mailbox by entering your username (sometimes your email address) and password
If you work for a company, your company email account will be set up and ready to go.

3.4. Junk mail. How to protect yourself from junk mail.

Junk mail

Very often, junk mail comes with a lot of unwanted advertising emails that take up a lot of your time to read. Most email programs have security features that separate junk mail from mail you really want to receive. The email program creates a folder to which unwanted emails are directed (e.g. Junk Email)

How to protect yourself from unwanted emails

It is not possible to prevent spam completely, but it is possible to reduce the amount of spam:

• ignore the spam you receive: do not reply to such emails
• Do not reply to emails requesting personal information (personal identification number, credit card details)
• Do not purchase from websites that are advertised in spam emails
• Do not open attachments to unsolicited emails, even if you see the address of a known sender in the header
• Do not forward emails that you are asked to forward or send to others - they may be fraudulent or act as a virus distribution system.

3.5. Self-assessment test

Answer the questions and find out if you know about email.

4. Google Drive and its tools

"Google Drive is simple: enabling internet users to store all the data they want on Google's servers. Given the potential resources of Google's server arrays, this means that users can essentially transfer the contents of their personal computer hard drive, however large, to a virtual Google Drive. This is convenient because it allows users to access and work on their data from any computer connected to the internet. Once uploaded to Google Drive, you can access your files on your desktop, mobile phone, tablet at drive.google.com or gmail.com. Data synchronisation software ensures that when we start editing a document on an office computer, we can make the necessary changes when we go to a client's place, for example, and access our Google Drive wirelessly, and then review the final document at home.

Photos, videos, documents and other important files can be uploaded to Google Drive. Free access to 15 GB of storage is available.

Applications. The drive has built-in applications that look a bit like standard MS Office applications. All changes are automatically saved and there is the possibility to share files.

Powerful search. "Google Drive allows you to find files faster thanks to its object and text recognition feature.

Preview. More than 30 file types can be opened directly in the browser, including HD videos, Adobe Illustrator and Photoshop, even if you don't have the program installed on your computer.

Work offline. If you're using Chrome, you can enable the Offline Drive option to create, edit and annotate documents, slides and drawings, and view spreadsheets when there's no network connection.

Chat, discussion, comments. It is possible to communicate with others by chatting in documents, spreadsheets and slides, or by posting comments on files and images. By writing a comment and adding a + to the front of the email address, the drive will send an email to this address, notifying the recipient that they can view the comment.

View history. "Google Docs, spreadsheets and slides are automatically saved. Creation and editing history can be viewed for other file types with a 30-day edit history, which makes it easy to see who made the changes and to restore previous versions.

How to use Google Drive for a step-by-step guide in this video.

Source: https://www.youtube.com/@Howfinity