RAM Computer Memory:

The acronym RAM stems from the fact that data stored in random access memory can be accessed – as the name suggests – in any random order. Or, put another way, any random bit of data can be accessed just as quickly as any other bit.

• The most important things to understand about RAM are that RAM memory is very fast, it can be written to as well as read, it is volatile (so all data stored in RAM memory is lost when it loses power) and, finally, it is very expensive compared to all types of secondary memory in terms of cost per gigabyte. It is because of the relative high cost of RAM compared to secondary memory types that most computer systems use both primary and secondary memory.
• Data that is required for imminent processing is moved to RAM where it can be accessed and modified very quickly, so that the CPU is not kept waiting. When the data is no longer required it is shunted out to slower but cheaper secondary memory, and the RAM space that has been freed up is filled with the next chunk of data that is about to be used.

In the Question:

Data in RAM can be  ___________

The Answer is modified, erased, or read.

Although many types of memory in a computer exist, the most basic distinction is between primary memory, often called system memory, and secondary memory, which is more commonly called storage.

The key difference between primary and secondary memory is speed of access.

There are three types of memories:

• 1. Secondary Memory:
• 2. Primary Memory:
• 3. Cache Memory

Secondary Memory:

This memory stores much larger amount of data and information for extended periods of time. Data in secondary memory cannot be processed directly by the CPU, it must first be copied into primary memory, i.e. RAM. It is the slower and cheaper from of memory. Secondary storage is not to store data and programs when they are not being processed. It is also non - volatile in nature. Due to this, the data remain in the secondary storage as long as it is not overwritten or delete by the user. It is a permanent storage.

Primary Memory:

The main memory of the computer is also known as RAM, standing for Random Access Memory. When power is lost, the information is also lost. It can be directly accessed by the CPU. The CPU will normally transfer the data to and from the main memory in groups of two, four or eight bytes, even if the operation is undertaking a single byte memory.  There are two key types of primary memory:

• RAM, or Random Access Memory: 
• ROM, or Read Only Memory

Cache Memory:

The cache memory is placed between the CPU and the Main memory. It is a fast speed memory ,which is expensive and faster than the main memory. It is used to store the accessed data and instruction of main memory.

In the Question:

Which of the following statement(s) is incorrect:

(i)There are only Two types of memory.  This statement is incorrect as there are three types of memories.

(ii) RAM memory is very fast. This statement is true.

(iii) Data in secondary memory can be processed directly by the CPU. .This statement is incorrect

The Answer is (i), (iii).

Hence the Option C is Correct.

Types of Memory

Although many types of memory in a computer exist, the most basic distinction is between primary memory, often called system memory, and secondary memory, which is more commonly called storage.

There are two types of memories:

• 1. Secondary Memory
• 2. Primary Memory

Secondary Memory:

This memory stores much larger amount of data and information for extended periods of time. Data in secondary memory cannot be processed directly by the CPU, it must first be copied into primary memory, i.e. RAM. It is the slower and cheaper form of memory. Secondary storage is not to store data and programs when they are not being processed. It is also non - volatile in nature. Due to this, the data remain in the secondary storage as long as it is not overwritten or delete by the user. It is a permanent storage.

Primary Memory:

The main memory of the computer is also known as RAM, standing for Random Access Memory. When power is lost, the information is also lost. It can be directly accessed by the CPU. The CPU will normally transfer the data to and from the main memory in groups of two, four or eight bytes, even if the operation is undertaking a single byte memory.  There are two key types of primary memory:

• RAM, or random access memory
• ROM, or read-only memory

In the Question:

Primary storage is _______ as compared to secondary storage. 

The Answer is Fast and expensive.