List (linked list, provides fast sequential access)
Stream (same as List, except that the tail is evaluated only on demand)
Vector (array-like type, implemented as tree of blocks, provides fast random access)
Range (ordered sequence of integers with equal spacing)
String (Java type, implicitly converted to a character sequence, so you can treat every string like a Seq[Char])
Map (collection that maps keys to values)
Set (collection without duplicate elements)