It's important to note that the traditional five-kingdom classification system (Animalia, Plantae, Fungi, Protista, Monera) is being challenged by newer classifications based on molecular data. In these newer systems, bacteria are placed within the domain Bacteria (along with archaea), and their classification is more complex and nuanced.

Here's a simplified explanation:

* Traditional: All bacteria were lumped into the Kingdom Monera.

* Modern: Bacteria are placed within the Domain Bacteria, which is a higher-level grouping than a kingdom. Within this domain, there are many different phyla, classes, orders, etc., representing the vast diversity of bacterial life.

So, while "Kingdom Monera" is still a common term, it's important to be aware of the updated classifications and the incredible diversity within the bacterial world.