internalFormat in glCompressedTexImage2D specifies format in texture or the format in OpenGL(GPU)?

internalFormat in glCompressedTexImage2D specifies format in texture or
the format in OpenGL(GPU)?

This is a little silly question but the link
(http://www.opengl.org/sdk/docs/man/xhtml/glCompressedTexImage2D.xml) says
it "Specifies the format of the compressed image data stored at address
data." which means the actual compressed texture image format. That is
what I thought.
Then why is it called "internal format"? Shouldnt it just be called Format?
Because Internal Format in glTexImage2D() means the format in which the
image data is stored in GPU internally.