StringFormat (Built-in Mathematica Symbol)

StringFormat["string"] attempts to determine what ImportString format could be used to import the string " string".

SyntaxQ (Built-in Mathematica Symbol)

SyntaxQ["string"] returns True if the string corresponds to syntactically correct input for a single Mathematica expression, and returns False otherwise.

TextData (Built-in Mathematica Symbol)

TextData[exprs] is a low-level representation of the contents of a textual cell.

ToLowerCase (Built-in Mathematica Symbol)

ToLowerCase[string] yields a string in which all letters have been converted to lowercase.

VerifyConvergence (Built-in Mathematica Symbol)

VerifyConvergence is an option to Sum, NSum, and similar functions that specifies whether convergence checking should be done.

VertexAdd (Built-in Mathematica Symbol)

VertexAdd[g, v] makes a graph by adding the vertex v to the graph g.VertexAdd[g, {v_1, v_2, ...}] adds a collection of vertices to g.

$BatchOutput (Built-in Mathematica Symbol)

$BatchOutput is True if output in the current session is being sent in batch mode, suitable for reading by other programs.

$MinNumber (Built-in Mathematica Symbol)

$MinNumber gives the minimum positive arbitrary-precision number that can be represented on a particular computer system.

Mathematical Functions (Mathematica Overview)

Naming Conventions Generic and Nongeneric Cases Numerical Functions

Numeric Quantities (Mathematica Tutorial)

Testing for numeric quantities. Pi is a symbol, so Pi+3 is not explicitly a number. It does however have a numerical value.