# Ephemeris
# Introduction
The ephemeris category provides blocks with calendar functionality. The blocks can be used to determine what type of day today is, or a number of days before or after today is. For example, a way to determine if today is a weekend, a bank holiday, someone’s birthday, trash day, etc.
Definition of holidays can be customised through the ephemeris.cfg file. See the Ephemeris configuration page (opens new window) for more information.
# Overview of the Ephemeris blocks
# Ephemeris Blocks
More about that topic can be viewed at 
Using Ephemeris information (opens new window)
# Holiday, weekend or weekday check
Function: this block checks if the given date is a holiday, weekday or weekend.
Type: boolean true or false
Examples
# Get the holiday name for a particular date
Function: Returns the holiday name for the given date.
Will return null if no holiday is found for the date.
Type: String
# Get the number of days until a specific holiday
Function: Return the number of days until the given holiday name, or -1 if the holiday is not found.
Type: number
Some holidays are already provided by default from openHAB. Additional holidays must be configured in ephemeris.cfg.