Letter of invitation A)What is an letter of invitation? a letter of invitation is written to invite a person for a professional or personal event personal occasions family reunion, birthdays etc business event: job interviews, business conferences, etc Invitation card letter of invitation formal less formalLetter of Invitation A) What is an letter of invitation? A letter of invitation is written to invite a person for a professional or personal event. personal occasions :family reunion, birthdays ,etc. business event : job interviews, business conferences, etc. Invitation card & Letter of invitation formal & less formal