Construction is everywhere you go – your home, office, school, where you play and shop and even the roads that get you there and back. Developers and owners typically hire contractors to build or renovate properties. Construction contractors often specialize in a product type, such as office buildings, shopping center or warehouse buildings. Each construction project requires skills in roofing, carpentry, electrical, plumbing, welding, heating and air, just to name a few. Craft professionals learn their trade through both formal and informal training programs. Formal apprentice programs combine on-the-job-training with classroom instruction making it possible to earn while you learn.