You can mine on Foxy-Pools using various mining software and connection methods.
Socket.IO and Websocket connections offer push support by keeping a constant connection to the server open, which can slightly improve the time for the miner to detect a new round started as well as drastically reduce the load on the pool.
HTTP Polling is the "classic" way of connecting to a Signa Wallet and thus was adopted by most mining pools. Miners poll for new mining info every x seconds. This connection method is considered legacy.
If you are new to mining please head over to the Getting Started Guide to learn how to setup mining with your HDDs!