Related to the thread What is our policy on ambiguous tags?, I am starting this thread, for the benefit of people who wish to call attention to tags that should be merged, synonymized, or other such actions. The hope is that if a proposal garners enough upvotes, moderators would take heed and act accordingly. Please keep it to one proposal per answer.
Here's another tag question: should we merge libraries and software into software, or is it worth keeping them separate? For instance, PETSc is a library, and Trilinos is a collection of libraries, but they've been referred to as software. Optimization solvers can be libraries, and are sometimes executables (the same solver might exist as both, too). However, Matlab is clearly software (even though you can call Matlab from a library, most people would not, and when you call Matlab from a library, it starts the Matlab engine). Mathematica is also clearly software, implying that we shouldn't subsume software under libraries. Thoughts?
Also, is there a way to define "is a" relationships between tags? Someone recently added the "solver" tag, which I think should not exist because it's too ambiguous. In that context, linear-solver was most appropriate, but it might be nice to also have algebraic-solver that could be used alone, but would implicitly include all questions tagged with linear-solver.
Please delete this misspelled tag: optimzation