Skillets are typically deeper than frypans, which makes them more suitable for dishes that call for more liquid or sauce. Its depth also allows you to add in more ingredients for one-pan meals that include vegetables and meat. All this without spilling out.
Skillets are the heavier option because of its thickness, the material used to craft it, and larger size. This extra weight allows skillets to distribute heat evenly and retain heat better, making it ideal for recipes that involve searing and braising.