Difference between f(x) and f(x,y)? I recently started doing calculus and came across terms such as f(x) and f(x,y). What is the difference between them? Are they the same thing?

No, they are not the same thing. $f(x,y)$ is a function of two variables $x$ and $y$, e.g., $f(x,y) = 3x + \sin(y)$. But $f(x)$ is a function of only one variable, e.g., $f(x) = x^3$.
