What's the difference between f"{x}" and "{}".format(x) in python?

I’m new to python, and I just want to know the difference between those examples.
Does it differ when it comes to the execution speed?

When do I use one of them instead of the other?

x: int = 64
print(f"Your Number is {x}")

and

x: int = 64
txt = "Your Number is {}"
print(txt.format(x))

Thank you in advance!

>Solution :

Python f-strings were added in 3.6. Therefore you should consider using format() if you need compatibility with earlier versions. Otherwise, use f-strings.

On macOS 12.1 running 3 GHz 10-Core Intel Xeon W and Python 3.10.2, f-strings are significantly faster (~60%)