The Prime Number Theorem is a theorem that describes the distribution of the primes. It says that the number of primes less than or equal to a real number $x$ is asymptotic to $\frac{x}{\ln x}$.
The Prime Number Theorem is a theorem that describes the distribution of the primes. It says that the number of primes less than or equal to a real number $x$, $\pi(x)$, is asymptotic to $\dfrac{x}{\ln x}$, or equivalently, the $n$-th prime is asymptotic to $n\ln n$.