Generating combinations is a common task when building websties and programs. In this article, we wil learn how to generate combinations in R.

To generate combinations in R, we can use the `conbn`

method which will generate all possible groups of k from n items. The signature of the method looks like `cobn(items, k)`

.

If we would like to generate all combnations of groups of 3 from the numbers 1-4, we can do the following:

```
combn(1:4, 3)
# [,1] [,2] [,3] [,4]
# [1,] 1 1 1 2
# [2,] 2 2 3 3
# [3,] 3 4 4 4
```

Each column in the output is a distinct group.

Now, we can do the same with string combinations using the following.

```
strings = c("A", "B", "C", "D")
combn(strings, 3)
# [,1] [,2] [,3] [,4]
# [1,] "A" "A" "A" "B"
# [2,] "B" "B" "C" "C"
# [3,] "C" "D" "D" "D"
```