The History section sets up History options:

HistoryCategoriesCategories that describe the type of note in History.
HistoryListingFontFont to be used when creating listings.
HistoryCategoryVisibleDisplays category and attachemnt indicator in the History.
LogCompletionWhen Things To Do, Appointments and Office Memos are marked completed, the system will automatically create a note in the History
CompletionCategoryCategory to set the History entry for items completed.
TTDCategoryCategory to set Things To Do completed. Overrides the CompletionCategory.
PhoneMessageCategoryCategory to set Phone Message completed. Overrides the CompletionCategory.
AppointmentsCategoryCategory to set Appointment completed. Overrides the CompletionCategory.
LogMergingCreate note in History when a Document or Form is merged.
MergingCategoryCategory to set the History entry for items merged.
DocumentCategoryCategory to set Documents merged. Overrides the MergingCategory.
FormsCategoryCategory to set Forms merged. Overrides the MergingCategory.
PacketCategoryCategory to set Form Packets created. Overrides the MergingCategory.
LogEMailCreate entry in History when an e-mail is sent.
EMailCategoryCategory to set the History entry for e-mails sent.
LogExternalCreate entry in History when an external document is added.
ExternalCategoryCategory to set the History entry for external documents.
HistoryReadOnlyOnce a History entry is saved, it cannot be modified.
HistoryReadOnlyAfterHistory entry will be set read-only after the amount of time, from the date and time of the entry, has passed.
ConvertBlockNotesConvert notes from previous versions automatically