Bootstrap containers are fundamental building blocks used to create responsive layouts. They provide a means to center your content and apply horizontal padding for alignment. Here's a basic example of how to use a Bootstrap container.

        

            
Hello, world!
            
This is a simple example of a Bootstrap container.
        
        

1. .container: A responsive fixed-width container.
2. .container-fluid: A full-width container that spans the entire width of the viewport.
3. .container-{breakpoint}: Responsive containers that change width at different breakpoints (e.g., .container-sm, .container-md).

• Containers are essential for creating responsive designs that adapt to different screen sizes.