name,objects_hr,arrows_hr DagCat,†-categories (dagger categories),†-functors (dagger functors) Hilb₀,Hilbert spaces,unitary operators Ω,the inhabited trees,tree maps I,two objects,the walking isomorphism (and two identity arrows) 2,two objects,the walking arrow (and two identity arrows) Feyn,Feynman diagrams,symmetries of Feynman diagrams SymmRel,sets,symmetric relations Surj,sets,surjections Quant,quantales,suplattice maps SupLat,suplattices,suplattice maps SupVect_k,super vector spaces over fields k,super linear maps SupLieAlg_k,Lie algebras over super vector spaces over fields k,super linear maps Spectra,topological spectra,spectrum maps Span(Grpd),groupoids,spans of tame functors Span(Set),sets,spans of functions CartSp,Cartesian spaces,smooth maps Man,smooth manifolds,smooth maps SMan,simplicial smooth manifolds,smooth maps LieGrp,Lie groups,smooth group maps Aut,regular (Moore) automata,simulations SimpCat,simplicially enriched categories,simplicially enriched functors SSet,simplicial sets,simplicial maps Met,metric spaces,short maps FinMet,finite metric spaces,short maps PseudoMet,pseudometric spaces,short maps LMet,Lawvere metric spaces,short maps SymLMet,symmetric Lawvere metric spaces,short maps CompMet,complete metric spaces,short maps Ban_k,Banach spaces over fields k,short linear maps FinHilb,finite-dimensional Hilbert spaces,short linear maps Hilb,Hilbert spaces,short linear maps BanAlg,Banach algebras,short linear maps NormGrp,normed groups,short group maps NormRing,normed (commutative) rings,short group maps BanRing,Banach rings,short group maps CompNormGrp,complete normed groups,short group maps SemiRing,semirings (rigs),semiring maps SemiLat,semilattices,semilattice maps SemiGrp,semigroups,semigroup maps CRing,commutative rings,ring maps Ring,rings,ring maps SRing,simplicial rings,ring maps Rex,finitely cocomplete categories,right exact functors AbCat,Abelian categories,right exact functors AdmRep,admissible domain representations,representable continuous maps Rel,sets,relations BiCat,bicategories,pseudofunctors Prof,categories,profunctors PL,piecewise-linear manifolds,piecewise-continuous maps PDiff,piecewise-differentiable manifolds,piecewise-continuous maps Perm,the natural numbers,permutations RT(K₁),the natural numbers,partial realizable maps RT(K₂),sequences of natural numbers,partial realizable maps Pfn,sets,partial maps FinOrd,the finite ordinal numbers,order-preserving maps Rng,nonunital rings,nonunital ring maps Cluster,partitioned sets,non-refinement-increasing maps Species,species,natural transformations Ho(Cat),categories,natural isomorphism classes of functors Ho(Grpd),groupoids,natural isomorphism classes of functors nCob,(n-1)-dimensional compact oriented manifolds,n-dimensional cobordisms MultiSet,multisets,multimaps PermCat,permutative (symmetric strict monoidal) categories,multilinear functors Operad,symmetric multicategories,multifunctors Pos,partial orders,monotone maps PreOrd,preorders,monotone maps Δ,the inhabited simplices,monotone maps Pros,preorders,monotone maps CMon,commutative monoids,monoid maps Mon,monoids,monoid maps Mod(Ab),modules of monoids in Ab (rings),module maps Meas,measurable spaces,measurable maps Mat_SR,the natural numbers,matrices over semirings SR Mat_R,the natural numbers,matrices over rings R Mat_k,the natural numbers,matrices over fields k Set,sets,maps Log,topoi,logical functors Ch.(Vect_k),chain complices of vector spaces,linear maps FinVect_k,finite vector spaces over fields k,linear maps Vect_k,vector spaces over fields k,linear maps TopVect,topological vector spaces,linear maps LieAlg_k,Lie algebras over vector spaces over fields k,linear maps SLieAlg_k,simplicial Lie algebras over vector spaces over fields k,linear maps FinVect_q,finite vector spaces over finite fields of order q,linear maps Lex,finitely complete categories,left exact functors PrCat,locally presentable categories,left adjoint functors DagCompCat,compact closed †-categories,lax monoidal †-functors MonCat,monoidal categories,lax monoidal functors SymCat,symmetric monoidal categories,lax monoidal functors BrMonCat,braided monoidal categories,lax monoidal functors SymmMonCat,symmetric monoidal categories,lax monoidal functors TracedSymmMonCat,traced symmetric monoidal categories,lax monoidal functors CompCat,compact closed categories,lax monoidal functors *Aut,star-autonomous categories,lax monoidal functors BoolAlg,Boolean algebras,lattice maps CompBoolAlg,complete Boolean algebras (CABAs),lattice maps CompLat,complete lattices,lattice maps DistLat,distributive lattices,lattice maps HeytAlg,Heyting algebras,lattice maps Lat,lattices,lattice maps Inj,sets,injections Op(FinCartSp),open sets of finite-dimensional Cartesian spaces,inclusions Idem,idempotent endofunctions,idempotency-respecting maps Hyp,finite directed hypergraphs,hypergraph maps Ho(Top),topological spaces,homotopy classes of continuous maps Ho(Eff),numbered sets,homotopy classes of computable maps Ab,Abelian groups,group maps FinGrp,finite groups,group maps Grp,groups,group maps NormAb,normed Abelian groups,group maps Tor,Torsion groups,group maps AbTor,Abelian torsion groups,group maps AbTorF,torsion-free Abelian groups,group maps SGrp,simplicial groups,group maps SAb,simplicial Abelian groups,group maps LieRing,Lie rings,group maps DirGph,directed graphs,graph maps Gph,undirected graphs,graph maps Quiv,quivers,graph maps G,the natural numbers,globe maps Topos,topoi,geometric arrows Cat,categories,functors Grpd,groupoids,functors RCat,restriction categories,functors Frm,frames,frame maps FinSet,finite sets,finite maps Field,fields,field maps PROP,monoidal product & permutation categories,eso strict monoidal functors CPROP,colored monoidal product & permutation categories,eso strict monoidal functors DblCat,double categories,double functors DGph,digraphs,digraph maps DGCAlg,differential-graded commutative algebras of vector spaces,differential-graded algebra maps DSet,dendroidal sets,dendroidal maps □,the inhabited cubes,cubical maps TopRing,topological rings,continuous ring maps AdicRing,adic rings,continuous ring maps AdicCRing,commutative adic rings,continuous ring maps TopMon,topological monoids,continuous monoid maps Comp,compacta (compact Hausdorff spaces),continuous maps Diff,differentiable manifolds,continuous maps Loc,locales,continuous maps Top,topological spaces,continuous maps TopMan,topological manifolds,continuous maps Haus,Hausdorff (T₂) spaces,continuous maps Tych,Tychonoff spaces,continuous maps Stone,Stone spaces,continuous maps STop,simplicial topological spaces,continuous maps SoberTop,sober topological spaces,continuous maps SpLoc,spatial locales,continuous maps Ste,stereotype spaces,continuous maps 1Type,homotopy 1-types,continuous maps TopGrp,topological groups,continuous group maps STopGrp,simplicial topological groups,continuous group maps TopCat,topologically enriched categories,continuous functors Eff,sets with computable equality,computable maps Ass,assemblies,computable maps KV,computable real numbers,computable maps EffAdmRep,effective admissible domain representations,computable continuous maps Mono,injections,commuting squares Sierp,maps,commuting squares SES(Ab),short exact sequences of Abelian groups,commuting diagrams CW,CW complexes,cellular maps Bimod(Ab),monoids in Ab (rings),bimodules of monoids in Ab (rings) Bij,sets,bijections Set*,pointed sets,based maps Top*,pointed topological spaces,based continuous maps Alg(Ab),algebras of monoids in Ab (rings),algebra maps CommAlg(Ab),commutative algebras of monoids in Ab (rings),algebra maps R+,non-negative real numbers,addition DCPO,directed-complete partial orders,Scott-continuous maps CPO,complete partial orders,Scott-continuous maps Poiss,smooth manifolds with Poisson structures,Poisson maps Circ,the natural numbers,Boolean circuits 2Cat,2-categories,2-functors 1,(is) the point,(is) the identity arrow