What is meaning of different symbols in image? I am learning about Deep Generative Models, tutorials all over the places use symbols and no one actually explaining the meaning of it. Can you please suggest the meaning of these terms?
In general in probabilities the symbol $\sim$ means "follows the distribution ..", for example:

$$X \sim N(3,7)$$

would mean that the random variable $X$ follows a normal distribution with mean 3 and std. dev. 7. In your example the symbol is used to define the notations apparently: the training data follows the distribution of the real data denoted  $p_{data}$ and the generated samples (whatever these are) follow the distribution calculated by the model denoted $p_{model}$. 

The point seems to be about the distinction between the real distribution of the data and the distribution obtained by the model: naturally one wants the latter to represent the former as accurately as possible, that's the job of the estimation algorithm.

An alternative very common notation would be $p(x)$ for the true (i.e. data) distribution and $\hat{p}(x)$ for the estimated (i.e. model) distribution.