q)help ` attributes| data attributes cmdline | command line parameters data | data types debug | debug - debugger commands define | assign, define, control and debug doth | .h namespace dotj | .j namespace dotq | .Q namespace dotz | .z namespace envvar | envvar - environment variables errors | error messages internal | negative bang - -n!x - internal system calls iterator | iterators/operators keyword | keywords/functions kill | kill - killing a q session lic | licenses - kdb+ license files operator | operators/functions save | save/load tables syscmd | system commands temporal | temporal - date & time casts q) q)help `operator @ Apply/At $ Cond ! Dict ? Find . Index/At Cast Enkey Roll, Deal Trap Tok Unkey Enum Extend Amend Enumerate Enumeration Select Pad Flip Splayed Exec mmu Display Simple Exec Internal Vector Conditional Update Delete + Add - Subtract * Multiply % Divide = Equals < Less Than > Greater Than ~ Match <> Not Equals <= Up To >= At Least | Greater, OR & Lesser, AND # Take _ Cut, Drop ^ Fill , Join q)