Nowdays people’s silhouettes are very popular vector files among vector stocks and designers. Because it is easy to make them and use, but they can make you graphics look really good looking & eye catching. Just look around you’ll see all kinds of silhouetes: gents and ladies, children and kids, teenagers and grown-ups, but most popular vector silhouettes are: girls, business man, dancing people.
Use human contours wise and it will help you to deliver hidden essence of your design message. Vector illustrations can be edited in many design software, for example: Xara, PMView, Corel Draw, Photo Styler, Macromedia Freehand, and certainly Any Adobe Software Indesign, Photoshop, Illustrator etc. can be used to open and edit vectors.
Adobe Illustrator my certain decision!