These are the various date and time related blocks available in the Time group of the block library:
date: extracts just the date portion of a date time value
dateTimeAdd: adds a duration (hrs, mins, or secs) to a dateTime
dateTimeSub: subtracts a duration (hrs, mins, or secs) from a dateTime
dateToNumber: converts the date into a number
dateToString: converts a part of date into a string
dtToDtAdd: adds one dateTime to another dateTime; results in a duration of minutes or seconds
dtToDtSub: subtracts one dateTime from another dateTime; results in a duration of minutes or seconds
now: gets the current dateTime for the host
siteDateTime: gets the current date and time for the site associated with the target Ref of the bline program
time: extracts just the time portion of a date time value
timeToMinutes: converts a time value to a number of minutes
timeToTimeAdd: adds one time to another time; results in a duration of minutes
timeToTimeSub: subtracts one time from another time; results in a duration of minutes
Some blocks have inputs or results in dateTime format, while others in simple time format. Blocks that require a time format input might not work if a dateTime value is used as the input.
dateTime example: 2019-07-04 14:39:15:149 (date and time with milliseconds)
time example: 14:39:15 (just hours:minutes:seconds)
The Blocks can be found in the Block Library in the Time group.