• While one (1) partition is the absolute minimum, a typical GNU/Linux installation will include at least two (2) partitions: the root partition (denoted as /) and the swap partition. During installation, most distros allow you to put all of your files on a single partition.
  
• To install Linux, you'll need the bare minimum of partitions. Up to a point, you are correct. The root partition is the only partition required to run gnu/linux.
• You can ignore almost all of it on a single-user desktop workstation. Most of the issues that necessitate so many partitions are not present in desktop computers for personal use. They advocate three partitions for a healthy Linux installation: swap, root, and home.

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