II. Put the words in brackets into the correct form.

1. If a computer can answer some question better and quicker than a man can do, it (to be) a man who formulates the questions.

2. If you asked what a software is, I (to note) it as “an applied though”.

3. It’s obvious that if there (to be) no computers. The progress of civilization wouldn’t be so rapid.

4. Producing of computer memory working model would have been possible in 1939, if many people (to credit) the invention.

5. If Herbert Simon and Alan Newell hadn’t succeeded in logic Theorist, someone else (to do) it.

6. If there is no adequate software, no computer (can) be used.

7. Had you backed up my opinion, the outcome (to be) more successful.

8. Were it permitted to our group to carry out the investigation, we ceratainly (to finish) it on time.

9.

Exercise 2 . Complete the sentences

III. Retell the text.

Unit IV.

I. Read and translate the text.

Hardware and Software

Computer hardware (usually simply called hardware when a computing context is implicit) is the collection of physical elements that constitutes a computer system. Computer hardware is the physical parts or components of a computer, such as the monitor, mouse, keyboard, computer data storage, hard disk drive (HDD), system unit (graphic cards, sound cards, memory, motherboard and chips), and so on, all of which are physical objects that can be touched (that is, they are tangible).^[1] In contrast, software is instructions that can be stored and run by hardware.

Computer software or simply software is any set of machine-readable instructions that directs a computer's processor to perform specific operations. Computer software contrasts with computer hardware, which is the physical component of computers. Computer hardware and software require each other and neither can be realistically used without the other. Using a musical analogy, hardware is like a musical instrument and software is like the notes played on that instrument.

Computer software includes computer programs, libraries and their associated documentation. The word software is also sometimes used in a more narrow sense, meaning application software only.

Software written in a machine language is known as "machine code". However, in practice, software is usually written in high-level programming languages that are easier and more efficient for humans to use (closer to natural language) than machine language. High-level languages are translated, using compilation or interpretation or a combination of the two, into machine language. Software may also be written in a low-level assembly language, essentially, a vaguely mnemonic representation of a machine language using a natural language alphabet. Assembly language is translated into machine code using an assembler.

VII. Retell the text.

Unit V.

I. Read and translate the text.

Coding Theory

Coding theory is the study of the properties of codes and their fitness for a specific application. Codes are used for data compression, cryptography, error-correction and more recently also for network coding. Codes are studied by various scientific disciplines—such as information theory, electrical engineering, mathematics, and computer science—for the purpose of designing efficient and reliable data transmission methods. This typically involves the removal of redundancy and the correction (or detection) of errors in the transmitted data.

There are four types of coding:

1. Data compression (or, source coding)

2. Error correction (or channel coding)

3. Cryptographic coding

4. line coding

Data compression and error correction may be studied in combination.

Source encoding attempts to compress the data from a source in order to transmit it more efficiently. This practice is found every day on the Internet where the common Zip data compression is used to reduce the network load and make files smaller.

The second, channel encoding, adds extra data bits to make the transmission of data more robust to disturbances present on the transmission channel. The ordinary user may not be aware of many applications using channel coding. A typical music CD uses the Reed-Solomon code to correct for scratches and dust. In this application the transmission channel is the CD itself. Cell phones also use coding techniques to correct for the fading and noise of high frequency radio transmission. Data modems, telephone transmissions, and NASA all employ channel coding techniques to get the bits through, for example the turbo code and LDPC codes.

The purpose of channel coding theory is to find codes which transmit quickly, contain many valid code words and can correct or at least detect many errors. So, different codes are optimal for different applications. The needed properties of this code mainly depend on the probability of errors happening during transmission.

Although not a very good code, a simple repeat code can serve as an understandable example.

Another concern of coding theory is designing codes that help synchronization. A code may be designed so that a phase shift can be easily detected and corrected and that multiple signals can be sent on the same channel

Another application of codes, used in some mobile phone systems, is code-division multiple access (CDMA). Each phone is assigned a code sequence that is approximately uncorrelated with the codes of other phones.^[

Another general class of codes are the automatic repeat-request (ARQ) codes. In these codes the sender adds redundancy to each message for error checking, usually by adding check bits

II. Retell the text.

Unit VI.

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