Alternatives to Dirac Delta?

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In one of its lower paragraphs, Wikipedia describes the dirac delta distribution as the limit of a sequence of zero-centered normal distributions.

https://en.wikipedia.org/wiki/Dirac_delta_function

I don't know much about "distributions" per se, but, are there other integrals of sequences of functions that converge to the dirac delta distribution? Or is this sequence unique in some way?

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You can try to prove the following yourself: Let $\chi$ be a continuous nonnegative function such that $$ \int_{-\infty}^{\infty} \chi(x)\,dx = 1 $$ and for each $\delta > 0$, let $$ \chi_\delta(x) = \delta^{-1}\chi(\delta^{-1}x). $$ Then for any bounded continuous function $f$ on the real line, $$ \lim_{\delta\rightarrow 0} \int_{-\infty}^{\infty} \chi_\delta(x)f(x)\,dx = f(0). $$