Hi danny MD,
They all mean "Agreed," or "Go Ahead," or "O.K."
Here's a quote from The Elements of Style, Second Edition (New York: MacMillan, 1972), by William Strunk, Jr., With Revisions, an Introduction, and a Chapter on Writing, by E. B. White.
The quote is taken from Chapter IV, which is titled, Words and Expressions Commonly Misused:
All Right, Idiomatic in familiar speech as a detached phrase in the sense "Agreed," or "Go Ahead," or "O.K." Properly written as two words --all right. The variant alright has not won general acceptance.The Elements of Style has been revised more than a few times since the 1972 Second Edition from which I quoted the above. (Updated editions appeared in 1979, and 1999; an illustrated edition followed in 2005). Check out the latest edition, Penguin Press HC, The (October 20, 2005), of this book at amazon.com:
Amazon.com: The Elements of Style Illustrated: William Strunk Jr., E.B. White, Maira Kalman: Books
Also, you might be interested in knowing that E. B. White, the editor and author of the book's Introduction and its Chapter on Writing (titled V An Approach to Style (With a List of Reminders) ), is the author of the well-known children's books:
Stuart Little (1945)
Charlotte's Web (1952)
The Trumpet of the Swan (1970)
White graduated from Cornell University in 1921, receiving a Bachelor of Arts degree. While at Cornell, Strunk was one of his professors.
You can read more about E. B. White and follow further links to Strunk at this Wikipedia entry:
E. B. White - Wikipedia, the free encyclopedia
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