By tradition, the oldest daughter had to be married first and only then the other daughters could. Today, this is not a common custom. Many religions have their own particular formal styles and codes of dressing for formal ceremonies. Traditional wedding clothes for the groom and the best man are either a grey or black suit or tuxedo.
Grooms often choose to wear a tuxedo on their wedding day.
His choice then sets the tone and style of the occasion for the guests. The colour of the dress is white or sometimes a light beige. The style varies depending on the time of the year of the wedding. The traditional bride may or may not have a veil. The veil can be any lenght from shoulder to down to the train.