a_date <- as.Date("2014-06-26")
a_date
# [1] "2014-06-26"
a_date + 1 # one day later
# [1] "2014-06-27"
another_date <- as.Date("08/28/1970", format="%m/%d/%Y")
another_date
# [1] "1970-08-28"
mode(a_date)
# [1] "numeric"
length(a_date)
# [1] 1
class(a_date)
# [1] "Date"
origin parameter specifies a starting date from which the number is added: dt <- as.Date(20, origin='2018-05-01'); dt; # # "2018-05-21"