Introduction

The HistoryCal project gives some precise definitions to certain words or phrases.

Date Signature

A code preceding a date to indicate the scheme and format of that date. A date signature is terminated with a '#' character. For example, "g:mdy# Sep 19, 1948"

Dual Dates

Including two ways of expressing an element of the date. Specifically, writing both the civil year and the historic year, separated by a '/' character.

Element

A date element is a part of the date text description. When reading a date's text, the elements are matched to the date's Fields.

Epoch

The mathematical starting point of a calendar system.

Era

The period of time covered for a given calendar scheme or part of a scheme.

Field

An part of a dates description, more formally the part of a Record which holds a single value.

Julian Day Number

The day count calendar used internally by HistoryCal. Abbreviated to jdn. Formally defined here.

HistoryCal Expression

A subset of the HistoryCal Script modified for easier input.

HistoryCal Script

The formal script language used by the Cal library. Files containing this language use the .hcs extension.

Multi-dates

Using more than one calendar scheme. Expressing the same date in a number of ways.

Pseudo Date

A text representation of a calendar scheme's output format. For example: "dd Mon yyyy".

Scheme Usable Range

The range covering the time the scheme was known to be in use.

Scheme Working Range

The range of dates for which conversions are possible.

Record

A collection of Fields which hold the values which define the date.