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A checkbox is probably the simplest Field Type in existence, yet it is still quite useful. Basically, a checkbox allows users to answer “yes” or “no” to a simple question.

A checkbox is allowed to show another Field when it is checked as well as when unchecked. For details, see Checkbox Settings.

• Labels and Tooltip
• Values and Auditing
• Grid Settings
• List and Column Settings
• About Me

The checkbox has five output formats.

• Full Field - This format returns nothing when the checkbox is unchecked, and returns CHECKED when the checkbox is checked.
• Checked - This format returns NOT CHECKED when the checkbox is unchecked, and returns CHECKED when the checkbox is checked.
• Field Label - This format returns nothing when the checkbox is unchecked, and returns the checkbox's Field label when the checkbox is checked.
• With Sub-Fields - This format returns “ - ” followed by the “Full Field” output format for its “Other Field When Unchecked” when the checkbox is unchecked, and returns “CHECKED - ” followed by the “Full Field” output format for its “Other Field When Checked” when the checkbox is checked.
• Sub-Fields Only - This format returns the “Full Field” output format for its “Other Field When Unchecked” when the checkbox is unchecked, and returns the “Full Field” output format for its “Other Field When Checked” when the checkbox is checked.

The checkbox Field Type can be filtered according to the standard two checkbox-type filters. To learn more about these filters, see the “Checkbox-type filters” section here.

The checkbox is also useful to hold a string of actions which need to be reused, much like a function. For instance, in a CRM application, you might want to track an opportunity's values as it progresses through its stages. Perhaps you'd want to create a related Opportunity History Item any time any of five different Fields were changed. You could create a checkbox called “Create Opportunity History” and attach an Item-Create Action (and all proper local Actions) to it and create a nested series of if-then statements (evaluations) to say:

if Field A changed

    check Create Opportunity History
 else if Field B changed
       check Create Opportunity History
    else if Field C changed
          check Create Opportunity History...

and so on, which is much simpler (and more efficient) than re-creating the Item-Create Actions under each if statement.