| Full Name | Portable Network Graphics |
| Extension | PNG |
| Type | Image |
| Mime Type | image/png |
| Format | Binary |
A PNG file is a two-dimensional image file format often used to store high-quality logos, icons, and other imagery. PNG files first emerged in the early 1990s as an alternative to the GIF format, which was in widespread use at the time. PNG files have garnered support over the years to at least equal or surpass that of the GIF format. You will find all modern image editing or viewing applications will support PNG files.
Part of the success of the PNG format is its use of special compression techniques that allow a high-resolution image to be compressed into a very small file size. The compression used in the PNG format is lossless compression, ensuring no image detail is lost when an image is saved to the PNG format.
Uses
The PNG format is ideally suited for storing images that require no loss of detail or have transparent areas, such as company logos and computer graphics icons. It is not suited for storing general photos as, due to the nature of the compression, it will result in very large file sizes. Other formats, such as JPEG, use a lossy compression method, and this format is better suited to full-color photographic images.
| Full Name | Wavefront |
| Extension | OBJ |
| Type | 3D Model |
| Mime Type | text/plain |
| Format | Text |
An OBJ file is a text-based file format used for the storage of 3D model data. The format was developed in the 1980s by Wavefront Technologies as a means to store the geometric mesh data associated with a 3D model. It has garnered widespread support in the following years, and you will find options to load from and save to the OBJ format in most modern 3D modeling applications.
As OBJ files are essentially text files, they can grow quite large when working with large and detailed 3D models.
Mesh Geometry
Within a 3D OBJ file are lists of vertices, mesh faces, face normals, texture coordinates, and more. The vertices, normals, and texture coordinates are stored in a continuous list and are indexed referenced within a separate list of mesh faces, ensuring optimal use of space within the file. A mesh face may contain three or more points, each of which can use a unique vector normal and texture coordinate.
