Lawyers practice law and they interpret and explain the law to the layman thus making it much simpler for us to understand it. Laws are integral for a society to function properly and make it orderly, civilized and just. Laws govern our everyday conduct, from how we use the internet to how we park our cars. Advocates represent their clients in the court and present supporting evidence.
Lawyers spend lots of time in research. They have to search for legal precedence, which are earlier interpretations of laws and the history of judicial decisions based on that particular law. Based on this precedence, they support their cases in the court and fight the case for their clients.
For more information on Law ,
http://www.schoolanduniversity.com/study-programs/criminal-justice/law
http://www.trafficgeyser.net/lead/law