In the following example
x = strsplit('30 min', ' ')
A list of the same length as x, the i-th element of which contains the vector of splits of x[i].
The explanation is that
strsplit expects a vector of input strings, each of which will be split into an array of strings, which are returned in the form of a list.
If you only provide this one string, it will be treated like it was the single entry of a vector. Thus, the result is a list with one entry (
x[]) and it's split contents (
x[]), as you've described.
x = unlist(strsplit('30 min', ' ')) and you'll get a character-vector, where