What is HALAL (Lawful) and HARAM (Prohibited)?

Muslims commonly use two terms to describe every subject as Halal or Haraam. Halal is a Arabic word which means permitted, lawful with respect to which no restriction exists, and the doing and consuming of which the Law-giver, Allah has allowed.
Haram means the opposite-unlawful or forbidden that which the Lawgiver absolutely prohibited; anyone who engages in it is liable to incur the punishment of Allah in the Hereafter as well as a legal punishment in this world.
Halal and haram are universal terms that apply to all facets of life. However, we use these terms only in relation to food products, meat products, cosmetics, personal care products, food ingredients, and food contact materials. There are some things which are not clear are considered questionable or suspect and more information is needed to categorize them as Halal or Haram. If a muslim consumes Haram foods and materials, he would be sinful.

Foods containing ingredients such as gelatin, enzymes, emulsifiers, etc. are often referred to as Mashbooh, (which means doubtful or questionable) because the origin of these ingredients are not known. Many of the foods are considered Halal except the following, which are Haram with out doubt.

Swine/pork and its by-products
Animals improperly slaughtered or dead before slaughtering
Animals killed in the name of anyone other than ALLAH (God)
Alcohol and intoxicants
Carnivorous animals, birds of prey and land animals without external ears
Blood and blood by-products
Foods contaminated with any of the above products are Haram.