Qiyamu-l Layl is the night prayer in general. Tarawih and Tahajjud both come under the category of Qiyamu-l Layl. Tarawih is the well known prayer. As for Tahajjud, then it is the night prayer that comes after sleeping. Any other general nafl prayers between Isha and Fajr come under the general category of Qiyamu-l Layl.