Linked from
The 23 pages that link to Singular value decomposition, each with the reason it gives.
Least squaresRelated: It reveals rank deficiency and supports robust least-squares solutions.
RegularizationRelated: Small singular values reveal directions where inversion amplifies noise.
Rank (linear algebra)Related: The number of nonzero singular values equals the matrix’s rank.
Matrix theoryBroader topic: It separates a matrix's principal directions from its scaling strengths.