The G1/2 standard (nominal 13 parallel screw) is used in most household household uses, so it can be connected to most water pipes, and it can be used with a variety of adapters, so it can be used for a wide variety of purposes.
Please note that the connection of the water pipe is the standard for tapers (R) even with the same diameter.In that case, you can use a conversion adapter or connect it with sealing tape.