we will see,

What is System on Chip (SoC) ?
So, 
Today we are leaving in the era of smartphones and tablets. 
And in the past decade technology has been evolved so much that using this smartphone and tablets we can do almost all the stuff that we are used to do with desktop and laptop. 

So using this smartphone and tablet do a stuff like gaming, web browsing, photo editing, creating documents, media streaming and many more things. 

And yet these devices are quite compact compared to the desktop and laptop. 
And yet they contain almost all the parts which you see inside the desktop and laptop. 
So,
Almost all the components that you see inside the motherboard of any laptop or desktop are integrated inside a single chip in the smartphone. 
So,
The entire system which is required to run a smartphone is integrated into a single chip. And that is known as a SoC or System on Chip. 

And thanks to the leading manufacturers like Qualcomm, Samsung, Apple, and MediaTek it is possible to integrate all the components inside a single chip. 
And sometimes if you see the size of this System on Chip, they are as small as the size of a coin. 

So,
Now the question is

How is it possible to integrate all the parts inside a single chip. 
So,
There are many reasons behind that. 
So,
Let's find out these reasons. 

The first reason is the processor which you see inside the smartphone are not as powerful as the processor which you find inside the desktop and the laptop. 

So,
Don't get me wrong. 

The processors which you see inside the smartphones are powerful enough, but if you compare them with the processors of desktop and laptop, the processors in desktop and laptop are quite powerful. 
So,
If you have seen any motherboard of any laptop or desktop, you must have observed that the processor is enclosed by the heat sink and the cooling fan. 

Because these powerful processors generate a lot of amount of heat. 
And they need some sort of cooling. 

So,
Just imagine the size of your smartphone if the same processor with all the cooling arrangement is fit into your smartphone. 
Forget about the cooling, if you put this processor inside your smartphone then your battery of the smartphone would die in just half an hour.

Because these processors are quite power hungry and require a lot of amount of power. So,
The fact is that processors which you see inside a smartphone and tablet are designed using a different architecture. 
So, 
The most of the processors which you see inside the smartphone and tablet are designed using ARM architecture. 

The System on Chip which is designed using this ARM architecture are quite powerful as well as power efficient.

One more thing is that operating system which is designed for these smartphones is optimized for this system on chips.

So,
Although on paper these smartphone processors don't look powerful compared to the desktop processors, but because of these software optimization, you hardly feel any lag when you operating these smartphones and tablets. 

Apart from that the advancement in the manufacturing technology has allowed us to integrate more and more transistors inside the same area. 

So, not only in the smartphone but in desktop and laptop also, you will see that many parts are integrated inside the same chip. 

So, these are the some of the reasons why you are able to integrate all the components inside a single chip. 

So, now as we know about what is the System on Chip, now let's find out 

What is inside this System on Chip. 
So, the first thing that you find inside the system on chip is processor and we have talked so much about this processor. 

So, the next thing that you will see inside the SoC is GPU. 

Which is known as Graphical Processing Unit. 

And it is responsible for all graphic related activity inside your smartphone or tablet. The next thing which you see inside the System on Chip is DSP. Which is known as Digital Signal Processor. 
And it is responsible for the activities related to audio processing, video processing and somewhat related to display.

So,
In some system on chip, you will find this audio and video processing module as a different module.
While in some cases, they are integrated inside the same module.
The next thing that you will see inside this System on Chip is the memory element. 
Which contains the storage memory, that is Read only Memory.

And the volatile memory, that is Random Access Memory.

So, now the next module that you see inside the system on chip is the connectivity module.
And this module ensures that the user has all kinds of connectivity. 

Like Wi-Fi, FM radio, USB, Bluetooth, sometimes GPS and Cellular Radios. 
So, these are the basic module that you will see inside the System on Chip.
Apart from this, some higher end System on Chip also contains some other modules, like module for the camera, location, Security, and the sensors. 
Now, sometimes due to the size constraint, it is not possible to integrate the Random Access Memory or RAM inside this System on Chip. 
So in such scenarios, the memory package is stacked above this System on Chip package. And they ate connected using this ball grid array. 
So, this kind of packaging arrangement is known as Package on Package arrangement (PoP). 

And this type of Package on Package arrangement reduces the cost as well as the size. 
Now in the scenarios, where memory is outside the System on Chip, you need to establish the connection between the CPU and the memory.
And that is done by the module known as Northbridge.

So, this module ensures the connectivity between the RAM and the CPU.
So, these are the modules you will find inside the today's System on Chip. 

So far this System on Chip technology is more or less limited to the smartphones and the tablets.
But in the near future, you will see this system on chips in almost all the devices and in all applications. 
So, now the question is what about the desktop and the laptop processors. 

So, the answer is, they will be still used in the applications were the size and power consumption is not an issue.
And you require an intensive amount of processing. 

So, 
The applications like super computers and the servers, they still will be preferred over the system on chips. 

So, I hope you understood what is System on Chip.

Thank You.........