What was distinctive about gothic cathedrals?

Some Gothic cathedrals, mainly in northern and eastern Germany, and southern France, used brick instead of limestone. The hard sticky material used to help keep the bricks and other materials together is called mortar, which is kind of like an older form of cement.

The distinguished features of gothic art styles in cathedrals are :

have many more windows, and much bigger windows,
and so they are not dark like Romanesque churches.
This is because the architects have learned some new ways
of making roofs and of supporting walls, especially the groin vault and the flying buttress.

Other features of Gothic Architecture include :
large stained glass windows that colorfully illuminate the interior.
This is common in cathedrals as light illuminated the religious images and
religious scenes in each window. Light may have been used in Gothic cathedrals
to evoke a spiritual feeling or other symbolic feeling.
A last interior feature is wide use of tapestry that highly decorated Gothic structures.

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