Concepts and vocabulary

This page explains the words used in DataJot. Understanding them prevents a lot of confusion, especially when you start using units, thresholds, or statistics.

Series

A series is the main container. It represents the value you want to track over time.

“Weight”, “Living Room Temperature”, “Coffee”, and “Rice Stock” are possible series. Each series has its own history, measures, chart type, and display settings.

Deleting a series also deletes the measures that belong to it. This is the action to check most carefully before confirming.

Measure

A measure is a dated numeric value. It always belongs to a series.

In a “Coffee” series, a measure can be 1 at 8:30 AM. In a “Living Room Temperature” series, a measure can be 21.4 at 6 PM. The date matters as much as the value because it drives the chart and statistics.

A measure can be added from the app, a widget, Shortcuts, or the local macOS HTTP server.

Category

A category groups several series together. It is not measured data, only organization.

For example, you can create a “Home” category for temperature, humidity, and air quality. Another “Habits” category can group coffee, cigarettes, or workout sets.

Deleting a category does not delete the series it contains. The series remain in DataJot and simply become uncategorized.

Unit and sub-unit

A unit describes a measurement family. A sub-unit describes a precise way to express that value.

For example, a mass unit can contain grams, kilograms, and tons. A series can then store and display values with the appropriate sub-unit.

Units are useful when you want consistent values over time or when several series reuse the same measurement structure.

Visualization configuration

A visualization configuration groups display choices: visible statistics, reference lines, thresholds, colors, and Y-axis bounds.

It can be used by several series. This is useful when you want the same display logic across similar tracking setups, such as several temperature series.

Threshold

A threshold helps identify a value based on a condition. It compares a measure or aggregated value with a limit.

For example, you can create a “High” threshold for values >= 25. If several thresholds can match the same value, DataJot uses the first matching threshold in the configured order.

Y-axis bound

A Y-axis bound limits the vertical scale of a chart.

It is useful when you want a more stable chart. For example, an indoor temperature chart can be easier to read if it stays within a consistent range instead of fully recalculating the scale for every period.