In Java, the byte keyword is used to declare a variable as a numeric type capable of holding an 8-bit integer within the range of -128 to 127. Here's an example:

byte books = 12;

This declares a variable named books as a byte and assigns it the value 12.

The byte keyword can also be utilized to specify the return type of a method, as demonstrated in the following example:

// Method returning the number of pages in a book
public byte getPagesInBook() {
    return 150;
}

This method, named getPagesInBook, declares a return type of byte and always returns the value 150. It could be used to retrieve a predefined month value within the valid byte range.