Gothic architecture first got its name during the Italian renaissance when the people considered all buildings of the middle ages barbaric and associated them with the savage Goths. But the title was later limited to the hardly barbaric architecture of the period between Romanesque and Renaissance.
Gothic architecture emerged from Romanesque architecture in the year 1144 ad. A Benedictine abbot called Suger was building a new church outside of Paris. He decided that he wanted something new and impressive. Suger wanted to make the Abby church of St. Denis so tall that it would seem to reach the heavens, and so amazing that everyone would remember it.
When people saw this new form of architecture, they were amazed. The Gothic style quickly spread. Towns and cities would not let their churches be outdone by churches elsewhere. They tried to build taller, longer, and more stunning churches than any other.
Many of the individual characteristics of gothic architecture, such as ribbed vaults and pointed arches, were also used in the Romanesque style. The way they were combined made gothic architecture unique. The ribs that held up the vaults were aligned so that they made diamond shapes on the ceilings, and had a good place for buttresses to be attached. Gothic architecture had each of the separate chambers connected without walls in-between each one. That gave the impression of a larger interior, and allowed the ceiling to be higher. The outward pressure of the vaults brought the need for buttresses to keep the building together. They were moved away from the side of the building, and were connected to the vault arching supports. This form of buttress became known as a flying buttress, and became widely used in gothic architecture.
Windows were very important. They were often stained glass with bible scenes. Each window could take months to complete, because some were as much as one-hundred feet tall. Gothic cathedrals had hundreds of windows, but the interior was usually dim. The colored glass did not allow as much light in as clear glass would.
It would be almost impossible to name all of the famous gothic cathedrals, so I will only tell you a few. Probably the most famous is the cathedral of Notre Dame de Paris. Begun in 1163, and standing nearly 115 ft. tall, it has all of the characteristics of gothic cathedrals including a huge rose window, a vaulted ceiling, and flying buttresses. Other famous gothic buildings include the Salisbury Cathedral, in England; and the Chartres Cathedral in France.