Making use of the apply family of functions can be done using the following steps:

1. Create a matrix and use apply to work on it:

m <- matrix(rep(1:10, 10, replace = TRUE), nrow = 10)

apply(m, 1, sum)
apply(m, 2, sum)

2. Use lapply over the vector:

numbers <- 1:3
number_of_numbers <- function(x){
 rnorm(x)
}
my_list <- lapply(numbers, number_of_numbers)

3. Use lapply and sapply over the list:

summary_function <- function(x){
 mean(x)
}
lapply(my_list, summary_function)
sapply(my_list, summary_function)

4. Use lapply over a dataframe:

list_from_data_frame <- lapply(iris, mean, trim = 0.1, na.rm = TRUE )
unlist(list_from_data_frame)