Internet, Web and Email
Basics
- The Internet is a worldwide network of networks. It began as ARPANET (1969, US Department of Defense).
- The World Wide Web (WWW) is a system of linked pages on the Internet, invented by Tim Berners-Lee at CERN (1989 to 1991). The Internet is the network; the Web is a service on it.
- ISP: Internet Service Provider. Bandwidth: maximum data rate, in bps (bits per second).
- Browser: software to view web pages. Chrome, Firefox, Safari, Edge. A search engine (Google, Bing) finds pages.
- HTML (HyperText Markup Language) is the language of web pages; HTTP is the protocol that carries them.
URL
A URL (Uniform Resource Locator) is the full address of a page: protocol://domain/path, for example https://jkedusphere.com/computer-knowledge. The domain names a site. Common extensions: .com (commercial), .org (organisation), .edu (education), .gov (government), .net (network), .in (India), .gov.in and .nic.in (Indian government).
Web terms
| Term | Meaning |
|---|---|
| Hyperlink | Clickable link to another page or place. |
| Home page | The first page of a website. |
| Bookmark / Favourite | Saved page address. |
| Cookie | Small file a site stores on your computer to remember you. |
| Cache | Saved copy of pages for faster loading. |
| Download / Upload | Receive a file / send a file. |
| Streaming | Playing media while it downloads. |
| Blog | Online journal. Wiki (Wikipedia): pages anyone can edit. |
| Incognito / Private mode | Browser does not save history or cookies on your device. It does not hide you from your ISP or the website. |
| Web 1.0 / 2.0 / 3.0 | Read-only web / interactive social web / decentralised and semantic web. |
- Email was developed by Ray Tomlinson (1971), who chose the @ sign. An address looks like name@domain.
- To: main recipient. Cc: carbon copy, visible to all. Bcc: blind carbon copy, hidden from other recipients.
- Inbox, Sent, Drafts, Spam (Junk), Trash. Attachments can be added.
- Phishing emails fake a trusted sender to steal information.
Keep practising
Notes are only half the work. Test yourself with questions and discuss doubts with other aspirants.
Prepared for exam revision from standard computer textbooks, Microsoft documentation and official sources. Features differ between Excel and Word versions (2016, 2019, 2021, 365) so check which version your exam follows. Found a mistake? Tell us.