My life depends on this But not really hah hah ..........

What are the differences in these two types !!?!??!

glMatrixMode(GL_MODELVIEW);
glMatrixMode(GL_PROJECTION);

GL_MODELVIEW is used to translate/rotate the viewpoint and place/orient the objects in your scene using glTranslate() and glRotate().

GL_PROJECTION is used to project the transformed vertices (after GL_MODELVIEW has beed used) onto the screen. GL_PROJECTION is used by the functions glOrtho(), glFrustum() and gluPerpective().