What does the Scala keyword "type" mean?

Question

Scala type system is driving me crazy. I'm starting to look for the source code for the base scala packages, and it repels my brain.

Can someone explain why we need to determine the type if Sequence is already an aka interface? I come from a Java job where type is a class or interface, but in scala the type seems to be more so.

package object scala {
  ....

   type Seq[+A] = scala.collection.Sequence[A] 
   val Seq = scala.collection.Sequence

 ....
 }

Answer 1

, "" Scala, . , scala , "Core scala. ". https://github.com/scala/scala/blob/2.11.x/src/library/scala/package.scala