Parzen density estimation

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Given a collection of data points $(x_1, ..., x_n)$, we assume they are drawn from some distribution with known parameters (say normal). Parzen density estimate is defined as $p(x) = (1/(nh))*\sum_{i=1}^n N((x-x_i)/h)$ ( or whatever function K from which the data points are drawn). I am having hard time interpreting this. The graph of the density estimate looks like a combination of many normal distributions, each connected to its neighbours. How to calculate this function of all other normal distributions?enter image description here Also, what exactly does this formula output? The probability of a new point x happening? Isn't this a continuous case, so the probability at a single point should be 0? $n$ is the number of data points and $h$ is a parameter which specifies how "wide" the kernel function should look ( for example, if it is uniform distribution, it will just be the width of the rectangle ). I would also appreciate any good remarks and clarifications on Parzen density estimation at all, because I am not entirely sure that I get the idea of it. Thank you.