OpenSCAD specified a value to be either a number, a boolean, a string, a range, a vector or or the undefined value. See [OpenSCAD types]. What is called a vector in the OpenSCAD types documentation is refereed to as a list here in order to distinguish between sequential lists of general or compound-values and [Euclidean vectors] of numbers.

type	description
boolean	a binary logic value (true or false)
number	a numerical value
string	an iterable sequence of of character values
list	an iterable sequential of arbitrary values
range	an arithmetic sequence
function	a function literal or variable containing functions

Special values

value	description
undef	a value with no definition
""	a string with no characters, the empty string
[]	a list with no element-values, the empty list
nan	a numerical value which is not a number
inf	a numerical value which is infinite

Specification conventions

For convenience, the flowing naming conventions are used to reference common data types used within the library.

name	description
value	any dataum that can be stored in OpenSCAD
scalar	a single non-iterable value
iterable	any value with iterable elements
empty	any iterable value with zero elements
bit	a binary numerical value (0 or 1)
integer	a positive, negative, or zero whole number
even	an even integer
odd	an odd integer
decimal	integer numbers with a fractional part
index	a list index sequence
datastruct	a defined data structure
data	an arbitrary data structure
map	data store of keys mapped to values
table	data store of values arranged in rows and columns

When a list has an expected number of elements '-n', the expected number is appended. When there is a range of expected elements, the lower and upper bounds are separated by a ':' and appended. When the list elements values are of a specified data type, that type is added before the name. See the following tables for a few examples.

name	description
list-n	a list of of n elements values
list-l:u	a list of l to u elements values
type-list	a list of elements with an expected type
type-list-n	a list of n elements with an expected type