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Humans have always been curious and creative. We learned to live together in communities and developed languages to communicate with each other. We also discovered many things and gained knowledge. But we faced a challenge: how to preserve this knowledge and pass it to the next generation?
We came up with a solution: writing and drawing. We used symbols and characters to represent information. We used different materials to write on, such as stone, leather, and wood. Later, we invented cloth and paper to make writing easier.
We can think of books as devices that store data. Books contain data in a form that humans can read. However, once a book is printed, we cannot change its data. So we can call it read-only memory.
We can also think of notebooks as devices that store data. We can write our homework in a notebook using a pencil. If we make a mistake, we can erase it and write the correct data. This way, we can change the data in a notebook.
This example shows the main functions of memory: reading, writing, deleting, and updating data.
Computer memory also has the same functions. But computer memory is different. Computer memory can only store data in binary form. Binary data is a sequence of 1s and 0s. Computers can understand binary data, but humans cannot.
To store data in computer memory, we need to convert data into binary form first. Then we need to write it in the memory.
To access data from computer memory, we need to tell the CPU what data we want. The CPU asks the memory for the data. The data travels from the memory to the CPU in binary form. The CPU tells the output devices, such as display or printer, how to show the data in human-readable form.
I will write another story on “How real-life data gets converted or represented into binary and back to human-readable form”.
Computer memory is made of very small components. Each component can store one bit of data by keeping the voltage state either high/low or on/off or 1/0. Many of these components together form the computer memory.
The size of computer memory depends on how many bits it can store or how many voltage states it can hold.
How do these small electronic components store the bit value by keeping the voltage state? I will answer this question in another story “The Power of FlipFlops”.
Computer memory has a structure of rows and columns of these small components. Each group of 8 components forms a byte. Each byte has a memory address like our house address. The CPU uses this memory address to read and write data from/to memory.
I will write another story on “How memory works” to explain more about computer memory.
Memory is very important for any computing system. Without memory, no computing system can function. There are different types of memory for different purposes. For example, registers (a kind of memory) inside the CPU store temporary data like intermediate results. RAM (Random Access Memory) stores instructions and data for running applications. Hard disks store permanent data. I will write a detailed story on “Types of Memory” to cover everything.