A PDF is a type of document and a JPG is an image file. Generally speaking, a PDF is going to be a document that is created from a word processing type document. A JPG is going to be a photograph or other image.
JPG to PDF :- Convert JPG Images to PDF Documents Online. Easily combine multiple JPG images into a single PDF file to catalog and share with others. No limit in file size, no registration, no watermark. This service automatically rotates, optimizes and scales down images, but keeping the original resolution.
The full form of PDF is Portable Document Format and JPG is Joint Photographic Experts Group