set message_list to {"Hello", "Hi", "Waz up", "Howdy", "Long time no see"} -- add or modify the text in quotes
set amount_of_greetings to the count of message_list
set message_number to random number from 1 to amount_of_greetings
set the_greeting to item message_number of message_list
display dialog return & the_greeting & "!" buttons {"OK"} default button 1 with icon 2