A dialogue is a scripted conversation. Real spontaneous language is actually full of common phrases and set conversations so dialogues are useful to help you into real live language.
A series of dialogs is a story that continues from one dialogue to the next. There are three levels:
Lower Intermediate Level: Hiromi’s Trip to Thailand
This is a story about a young Japanese woman’s vacation in Thailand. It has many simple, practical phrases for travel. You can listen and read at the same time as you follow the story.
Intermediate Level: Miyako’s Education
This is a story about an Australian exchange student at a Japanese university. He meets a passionate young Japanese woman who loves to learn.
Upper Intermediate Level: A New Life in Mosquito City
This is a story about a man who migrates to another country to start a new life. These dialogues are different from the others. They are not scripted. They were acted out by voice actors and the transcripts were added later.