No. They know when they were born.
Birth date is THE day you were born. Birthday is more like an anniversary of that date. So, for example, 8 Feb would be your birthday while the 8 Feb 1986 would be your birth date.
You should celebrate Christmas if you are a Christian - it's Christ's birthday (NB the date is 'conventional' - the real date of his birth is unknown).
You can ask someone for their date of birth by saying, "When is your birthday?" or "What is your date of birth?"
The words for birthday and date of birth in Esperanto are naskiĝtago and dato de naskiĝo respectively.
Date=D. Of=O. Birth=B. Date of Birth=D.O.B.
D.O.B is a short for Date Of Birthday or Date of Birth. D.O.B is shortly put for date of birth
His birthday.
Her date of birth is unknown.
Happy birthday
date of birth is when you were actually born birthday e.g. 12/4/1977 is just a celebration of your birth date each year after you are born .e.g 12/4/1999. No offense but you need to get out more.
her date of birth was in July,201988