Thanks, Wikipedia

Wikipedia is great. I love that it exists, though I’ve only occasionally contributed to it. But I’m hardly the first to notice that it sometimes fails for the general reader.

Here, for instance is a section from the entry for “Chebyshev polynomials”:

In 1952, Cornelius Lanczos showed that the Chebyshev polynomials are important in approximation theory for the solution of linear systems; the roots of T_n(x), which are also called Chebyshev nodes, are used as matching points for optimizing polynomial interpolation. The resulting interpolation polynomial minimizes the problem of Runge’s phenomenon and provides an approximation that is close to the best polynomial approximation to a continuous function under the maximum norm, also called the “minimax” criterion. This approximation leads directly to the method of Clenshaw–Curtis quadrature. (internal citations omitted)

I’m sure this makes sense if you know what Chebyshev polynomials are…in which case you probably wouldn’t look it up in an encyclopedia.