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# Architecture

<img src="/files/NZdNI3qwEgu8ZASgaHq2" alt="" data-size="original">

* The Linux kernel is monolithic in nature.
* System calls are used to interact with the Linux kernel space.
* Kernel code can only be executed in the kernel mode. Non-kernel code is executed in the user mode.
* Device drivers are used to communicate with the hardware devices.