Updated to version 2024-04-16: 09894 (replaced "a identity element" with "an identity element")
28539 (expanded the section about notation, separated the section about products and sums into two sections and expanded the tensor product section, reworded the comparison between bordism homology and singular homology, separated the section about torsion into a section about abelian groups and a section about compact manifolds and slightly expanded both of them, added a section reviewing the definitions of ring and principal ideal domain and field, added sections about cohomology groups and cohomology rings, added sections about (co)homology with coefficients in a field, added a section about cartesian products of spheres)
61813 (added a cross-reference for the direct product of two groups, updated publication info for one reference)
92035 (added another definition of semisimple for compact connected Lie groups, added a footnote defining semisimple for not-necessarily-compact Lie groups, added a section with examples for a general structure theorem, added a section about maximal tori and rank, added a sentence relating the rank to the notation, added sections about homology groups and torsion, added a section about cohomology rings and their relationship to homology groups, changed "group" to "compact topological group" in the footnote about Tannaka-Krein duality and removed an unhelpful reference)