Onboarding is a challenge for many companies. Remote organizations often create a handbook to help during this step.
A handbook should be a single source of truth for your company. A place where your employees go when they have questions about how things work in the organization.
Some companies have very detailed handbooks. GitLab's handbook, for example, would have more than 5,000 pages if printed. Having it online, however, allows for it to be indexable and searchable, making it easier to find the right information.