I. Read the text and make the plan.

It is interesting to note that memory, one of the basic components of the computer, is often called storage. It stores calculation program, the calculation formulae, initial data, intermediate and final results. Therefore, the functions of the computer memory may be classified in the following way. Firstly, the computer memory must store the information transmitted from the input and other devices. Secondly, memory should produce the information needed for the computation process to all other devices of the computer.

Generally, memory consists of two main parts called the main, primary or internal, memory and the secondary or external memory. The advantage of the primary memory is an extremely high speed. The secondary memory has a comparatively low speed, but it is capable of storing far greater amount of information than the main memory. The primary storage takes a direct part in the computational process. The secondary storage provides the information necessary for a single step in the sequence of computation steps.

The most important performance characteristics of a storage unit are speed, capacity and reliability. Its speed is measured in cycle time. Its capacity is measured by the number of machine words or binary digits. Its reliability is measured by the number of failures per unit of time.

План в питальній формі.

1. What is memory?

2. What is the function of memory?

3. What are the main parts of memory?

4. What are advantages and disadvantages of a storage unit?

5. What are their functions?

6. What are performance characteristics of the main and secondary memory?

7. What units are performance characteristics measured by?

План в називній формі.

1. The definition of memory.

2. The main functions of memory.

3. Classification of memory.

4. Advantages and disadvantages of memory components.

5. The functions of memory components.

6. Performance characteristics of memory.

7. The units for measuring the performance characteristics of memory.

План в тезисній формі.

Memory is one of the basic components of the computer.

Memory stores initial data, intermediate and final results.

It produces the information needed to other devices of the computer.

Memory consists of the main (internal) and the secondary (external) storage.

The main memory has high speed, but small capacity; the secondary memory possesses lower speed but greater capacity.

The main memory performs computation; the secondary memory provides information sequentially, step by step.

The performance characteristics — speed, capacity and reliability — are measured by cycles, binary digits and the number of failures per unit of time.