This summary is not the rule. The rule text controls.
If you're involved in a civil case going to trial, you and the other side can agree to have a smaller jury than the usual eight people. Both sides have to consent to this change.
You can also agree that the jury doesn't need a unanimous decision. For example, both sides could agree ahead of time that a verdict only needs a certain number of jurors to agree, like six out of eight, instead of requiring everyone to agree.
This gives people involved in a lawsuit some flexibility. It only works if both sides sign off on it. Without an agreement, the standard jury rules apply.