The function closure model can be used to create functions that "carry around data with them.

For simple scatter plots, plot.default will be used.

The if/else statement returns, as its value, the value of the statement that was selected.

If value is too large or too small NULL is returned.

Programmers can create their own custom conditions if they want.

Primary tools are mainly used for debugging R code.

No statement below next in the current loop is evaluated.

Vectorize() function does not preserve the invisibility of the return value.

The results of applying the function over the subsets are then collated and returned as an object.

Functions have named arguments which can optionally have default values.