Two Formatting Steps

Many PC users don't realize that formatting a hard disk isn't done in a single step. In fact, three steps are involved:

1. Low-Level Formatting: This is the "true" formatting process for the disk. It creates the physical structures (tracks, sectors, control information) on the hard disk. Normally, this step begins with the hard disk platters "clean", containing no information. It is discussed in more detail here.
2. Partitioning: This process divides the disk into logical "pieces" that become different hard disk volumes (drive letters). This is an operating system function and is discussed in detail in its own section.
3. High-Level Formatting: This final step is also an operating-system-level command. It defines the logical structures on the partition and places at the start of the disk any necessary operating system files. Read more about it here.

As you can see, two of the three steps are "formatting", and this dual use of the word is a big part of what leads to a lot of confusion when the term "formatting" is used. Low-level formatting is performed at the factory when the drive is manufactured; it is not something an end consumer can (or will ever want to) do.

Next: Low-Level Formatting