SVG stays sharp when it scales
Vector shapes can be redrawn at different sizes without the blockiness associated with enlarging a raster image. That makes SVG especially useful for logos, icons, diagrams and other shape-based graphics.
PNG is predictable for pixel-based output
PNG is a lossless raster format with transparency support. It is useful when you need fixed pixel dimensions, compatibility with raster-only software, screenshots or graphics whose detail is fundamentally pixel based.
Why convert SVG to PNG?
A PNG export can be useful when a destination does not accept SVG, when you need an exact raster size, or when you want to freeze the rendered appearance of a vector asset. Keep the original SVG if you may need to resize or edit the vector later.