Russia 7 класс Informatics (basic)
Chapters: 3
1. Digital literacy
Computer as a universal device · Software and data · Files and folders · Computer networks · Online safety and ethics
- Basic Computer Organisation – A computer system has hardware (parts you can touch) and software (instructions). Input devices bring data in, the CPU (ALU + Control Unit + registers) processes it, and output devices give results. Memory forms a ladder: registers and cache are tiny and fastest, primary memory (RAM, ROM) holds running programs, and secondary storage (HDD, SSD, pen drive) keeps data permanently. Memory is measured in bits and bytes: 8 bits = 1 byte, and each bigger unit (KB, MB, GB, TB, PB) is 1024 times the one before.
- File Management: Files, Folders, Paths and Backups – A file is named data; its extension tells its type. The operating system keeps files in folders that form a tree, and a path is the route from a drive to a file. Good file management means clear names, a logical folder plan, the right drive (local, external, network or cloud), regular backups (3-2-1 rule), archiving old work and protecting files from malware.
- Computer Networks and How the Internet Works – A network is a group of devices linked to share data. Each device has an IP address. Data is cut into numbered packets. Routers pass each packet hop by hop towards its address, and TCP puts the packets back in order. DNS turns a website name into an IP address. Clients ask, servers answer. Firewalls, passwords, updates and encryption keep a network safe.
- How Networks Grew and How Data Travels – A computer network is a group of connected devices that share data. Networking began with ARPANET (1969), grew into NSFNET (1980s) for universities, and joined with other networks to become the Internet, a network of networks. Every data communication has five parts: sender, receiver, message, communication media and protocol. Bandwidth is the range of frequencies a channel can carry (in Hz); data rate is how many bits travel per second (bps). Every device on a network has an IP address. Data can move by circuit switching (a fixed path is booked first) or packet switching (data is cut into packets that travel on their own).
- Cyber Crime and Cyber Safety – Cyber crime is any crime that uses a computer, phone or the internet as a tool or target. Common forms: hacking (breaking into a system without permission; ethical hackers test security with permission), eavesdropping (secretly intercepting communication), phishing (fake emails, SMS or websites that trick you into giving passwords, OTPs or card details), ransomware (malware that locks or encrypts files and demands money), cyber trolls (people who post provoking, offensive messages) and cyberbullying (harassing, threatening or humiliating someone online). Malware includes viruses (attach to files and spread), worms (spread by themselves), trojans (look useful but open a back door), spyware and adware (unwanted pop-up ads, often tracking). Safe browsing: https sites, updated software, antivirus and firewall, no unknown links or downloads. Identity protection: strong unique passwords, two-factor authentication, never sharing OTPs, careful sharing of personal details, and logging out on shared devices.
2. Theoretical foundations
Information and processes · Alphabets and binary code · Information volume · Text encoding · Image and sound encoding
- Information Theory – Information is something that removes uncertainty. We measure it in bits: one bit is the answer to one fair yes/no question. If N outcomes are equally likely, the information is I = log2 N bits (Hartley). If outcomes have different probabilities, the average information is H = −Σ p log2 p bits (Shannon). Information is created, stored, processed and transferred through a channel that may add noise.
- Number Systems and Encoding – A number system is a way to write numbers using a set of digits and a base. Decimal (base 10) uses 0–9, binary (base 2) uses 0 and 1, octal (base 8) uses 0–7, and hexadecimal (base 16) uses 0–9 and A–F. To go from decimal to any base, divide repeatedly by the base and read remainders bottom to top; for fractions, multiply by the base and read the integer parts top to bottom. To go to decimal, multiply each digit by its place value and add. Binary ↔ octal uses groups of 3 bits, binary ↔ hex groups of 4. Text is stored with encoding schemes: ASCII (7-bit, 128 characters), ISCII (8-bit, Indian scripts) and Unicode (every script), stored as UTF-8 (1–4 bytes) or UTF-32 (4 bytes).
- Data Representation: How Computers Store Numbers, Text, Images and Sound – Data is raw facts; information is data given meaning; knowledge is information we can use. A computer stores all data as bits (0 or 1). 8 bits make a byte, and 1 kB = 1000 bytes, 1 MB = 1000 kB, 1 GB = 1000 MB, 1 TB = 1000 GB. Numbers are stored in binary, where place values double: 1, 2, 4, 8 and so on. Text uses a character set: in ASCII 'A' is 65; Unicode covers every script. A bitmap image is a grid of pixels; size = width × height × colour depth. Sound is sampled: size = sample rate × bit depth × seconds. Vector images store shapes instead of pixels. Compression makes files smaller: lossless keeps every bit, lossy throws some detail away.
3. Information technologies
Text documents · Computer graphics · Multimedia presentations
- Word Processing: Making Clear, Well-Formatted Documents – A word processor (like LibreOffice Writer, Microsoft Word or Google Docs) is a program for typing, editing, formatting, saving and printing text documents. You change letters with character formatting (font, size, bold, colour), whole paragraphs with paragraph formatting (alignment, spacing, indents, lists), and the whole document with page setup and styles. Styles let the program build a table of contents automatically. You can add tables, pictures, headers, footers, page numbers, footnotes, citations and a bibliography, and use mail merge to make many personal letters from one template.
- Digital Presentations – A digital presentation is a set of slides shown on a screen to support a talk. Good presentations are planned first (purpose, audience, storyboard). Each slide has one idea: a short title, a few key words, and a picture, chart or diagram that helps. Use a consistent design (slide master or theme), strong colour contrast and large fonts. Add graphics, charts, audio, video and hyperlinks only when they help the message, and give credit for images you did not make. Use transitions and animations sparingly. Finally rehearse with speaker notes, run the slide show, and share or print it in the right format (PDF, video, handouts).