A professional headshot can be on a backdrop like a grey or black background, or even outside. If you work in a more casual industry or don't wear a suite and tie then a more casual yet still professional headshot may be the best way to go. Either way you'll present your best face to the world, though a more causal headshot gives at more friendly and approachable vibe. I like to say retouching a pictures makes you appear the way you do to the world. A good headshot is a realistic likeness, looking neither younger nor older than you do in person. Professional hair and makeup for women also adds to the polished look. You won't take headshots too often so it's worth the investment to make sure you get a great image to use for work and professional connections like LinkedIn.