 
[47Xxx]  Operator theory
 [47Axx]  General theory of linear
operators
[47A20]  
Dilations, extensions, compressions 
[47A30]  
Norms (inequalities, more than one norm, etc.) 
[47A50]  
Equations and inequalities involving linear
operators, with vector unknowns 
[47A68]  
Factorization theory (including WienerHopf and spectral factorizations) 
[47A99]  
None of the above, but in this section 
 [47Bxx]
 Special classes of linear operators
[47B35]  
Toeplitz operators, Hankel operators, WienerHopf operators 
[47B37]  
Operators on special spaces (weighted shifts, operators on sequence spaces, etc.) 
[47B65]  
Positive operators and orderbounded operators 
 [47Hxx]
 Nonlinear operators and their properties
[47H05]  
Monotone operators 
[47H06]  
Accretive
operators, dissipative operators, etc. 
[47H09]  
Nonexpansive mappings, and their generalizations (ultimately compact mappings, measures of noncompactness and condensing mappings, $A$proper mappings, $K$set contractions, etc.) 
[47H10]  
Fixedpoint theorems 
 [47Jxx]
 Equations and inequalities involving nonlinear operators
[47J20]
 
Variational
and other types of inequalities involving nonlinear operators 
 
