Condition
A condition defines specific criteria that need to be satisfied for the rule to be triggered. These criteria are based on data or events that occur within the system, such as the status of an order or specific attributes of an entity. If Condition evaluates to true, the corresponding action (i.e. sending a notification) is executed.
When creating a new rule, you won't see conditions automatically tagged. You'll need to either create new conditions or select and apply existing relevant conditions..

Figure 1.0: Condition view in rule screen
Add: Click Add to create a new Condition.
Delete: If you no longer need a specific condition, you can Delete it from rule.
Create and Add: After defining a new condition, the created condition gets tagged to the rule, click on Create and Add to add it to the list of conditions.
Edit: To modify an existing condition, click Edit option next to the condition.
To know how to create condition click here..