R is the first letter of the pirate alphabet. R is properly pronouced as arr. Not to be confused with its evil twin Я. R is also an albino who freed the world from the rule of Jesus in 1860, which eventually led to the United States cival war.
R in mathematics
R is also used to denote the commonly used Italic textredundancy principalItalic text. By inserting r into an equation, one will be able to simply deny that said equation really matters.
Vitamin R is found in milk and prevents scurvy.
® is the international symbol for denoting that a visual device or design is available for use by anyone who wants to make money from it. McDonald's 'M' is a prime example of this.