The Scanner class lets you read values from the keyboard without using Java's console input. Java's console input is slow, and so is its redirection. Scanner is faster and more convenient, so Scanner should be used in place of Java's console input. Scanner uses Java's regular input stream, so it can be chained with other parsers. Scanner is also easier to use than Java's console input. Scanner has three main subclasses, namely, BufferedReader, InputStreamReader, and FileReader. The most general one is BufferedReader. BufferedReader can read anything that can be read by InputStreamReader, and it has one big advantage: buffer. The buffer can hold one line at a time. An input stream has no buffer at all: when you call next(), it returns the value. This means you have to collect the values before you can do anything with them. Scanner does it for you.