Bridges+notes

__Bridges. __

**__Bridges:__** they are structures that connect one part of a place to another for people and vehicles to get across an obstacle or long distances easily and in a shorter time. The design will vary depending of its use and its materials. Usually bridges are made of wood, concrete, steel, bricks, stone, etc.

__The beam bridge: __ It is the earliest and simplest king of bridge; it is made of a simples beam supported at the end of both sides but unsupported in the middle. Most simple beam bridges are made of wood laid on stones supports. Lately these bridges have been made from steel or concrete, depending on how long it has to be and the weight it is going to support.  
 * __Types of bridges: __**

__The arch bridge: __ These bridges are formed by a semicircle shape. They where originally built of stone or brick. This kind of bridge dissipates the weight from the center of the deck to the abutments. 

__The suspension bridge: __ A suspension bridge is one where cables are strung across the obstacle and the deck is suspended from these cables. Modern suspension bridges have two tall towers through which the cables are strung. For suspension bridges steel cables are commonly used.

 The importance of a bridge in a town, city, etc., is that it communicates to different places and make possible for people to go to one place to another and interact with different cultures, get stuff that they won’t find on their own homeplaces, etc. The construction involves precision, hours of work and physics knowledge.