Some formats are definitely right for a particular task, while some are certainly wrong.
There are three basic types of graphics file formats. Bitmap files are typically created by image-editing programs such as Adobe Photoshop, or by the software you use to run your scanner. Vector files contain sets of instructions for drawing objects - typically geometric shapes such as lines, ellipses, polygons, rectangles, and arcs. Vector files are typically created by CAD programs such as Autocad. Metafiles can contain both vector and bitmap graphics, but they don't have to have both - sometimes you'll find metafiles that contain only an image, for instance.