Usually, when installing any Linux system, you can choose to automatically partition the disk, for example, Ubuntu 18.04 automatically creates two partitions – the root and boot, but you can partition the disk if you wish.
I will give a list of sections and briefly describe them:
/swap – The swap partition, when the RAM is busy, data starts to be written to this partition, usually it is located at the beginning of the disk because there is less delay for the hard disk drive. Size SWAP=RAM*2, if there is a lot of RAM, then SWAP can not be created or created equal to RAM or half RAM. It can also be created with a file in the root partition, for example, as I described in this article – How to create SWAP in Linux
/ – This is the root partition. Most important, all subsequent sections are mounted on it and it stores the most important files of the operating system.
/boot – Contains the kernel of the operating system and files to boot.
/usr (user) – All important user programs and libraries.
/tmp (temp) – The section contains temporary files, it is automatically cleared after restarting the operating system.
/var (variable) – Directory for frequently modified files, such as logs, cache, email, web server files, etc.
/opt (optional) – Directory for additional software.
/home – User home directories.
Depending on your needs, you can place directories in different sections, for example, move the /home directory to a separate section so that if it is full with user data, free space will remain in other directories and this will not affect the stability of the operating system.
Or, for simplicity, you can create one root partition and mark up the bootloader and all other directories in it.