k
Symbol  Format  Data 

k  Code Point 
U+006B 
TeX 
k 

SVG 
The Latin letter k is used in math as a variable. It commonly appears as an index variable for matrices along with the other letters i, j, and l.
The capital Latin letter K.
A variable is a symbol that represents an unknown or indeterminant quantity. Variables can represent numbers, vectors, or other mathematical objects, depending on the context.