Java Database Connection (JDBC)

I don't know why people don't use Google for these types of Codes. Most of the people told me that"Help me in Connecting Java with Database". I always told them use Google for these types of works. Mostly they reply I used Google but I got some error instead of checking erro in their code. I just copy my files and shre with them. They always think that I had did something great but what I did was copy my old files and paste to them.

How JDBC connection works ?