What are SVG files?
SVG stands for scalable vector graphics. It’s a scalable, open format file that defines graphics in Extensible Mark-up Language or XML. Scalable here means SVG graphics are typically used to share images on the web because they retain their quality when very large or very small.
Because SVG is a vector graphic format, Photoshop will automatically convert the file to a raster image when it’s imported. If you’re using Adobe Illustrator, you can still work with it in a vector image format.
What are PNG files?
PNG stands for portable network graphics. PNG is a raster graphics format that allows for lossless data compression. That means it allows the original data to be completely reconstructed from only the compressed data. PNGs are ideal for line drawings, text files and simple graphics.
As a raster graphics file type, PNGs are smaller and because they use less system memory, they load faster and are easier to work with than SVG files. The downside is that they don’t retain their quality when scaled up or down. If you use a PNG file in larger dimensions than the original file, individual pixels will start to show.