why IBM is called "the big BLUE" ??

Answer 1

Here's IBM's official answer from their own public relations website,

Q. "What is the origin of the term "Big Blue?"

A. The term "Big Blue" as a reference to IBM did not originate within the company. When the term first began appearing in the press during the early 1980s, IBM employees continued to refer to IBM as they always had -- and have since -- most typically, "IBM" or "the business" or "the company." Some writers have suggested that the "Big Blue" expression is related to the blue covers on the IBM mainframes and similar products of the 1960s. Of course, "Blue" can now be found in the names of some of IBM's supercomputers, such as Deep Blue, Blue Pacific and Blue Gene." http://www-03.ibm.com/ibm/history/reference/faq_0000000068.html

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And here is a well-researched answer about the same question that was posted on Google Answers,

"The first reference in print to IBM as "Big Blue" appears to be a June 8, 1981 article in Business Week magazine with the title "NO. 1's AWESOME STRATEGY". The phrase appears roughly midway through the article:

"No company in the computer business inspires the loyalty that IBM does, and the company has accomplished this with its almost legendary customer service and support. Other computer makers, in fact, measure their own service and support capabilities against what IBM provides. As a result, it is not uncommon for customers to refuse to buy equipment not made by IBM, even though it is often cheaper. "I don't want to be saying I should have stuck with the 'Big Blue,' " says one IBM loyalist. The nickname comes from the pervasiveness of IBM's blue computers."


From the context, it appears that "Big Blue" may already have been in colloquial use at the time. But according to a search on LexisNexis, this is the earliest use I could find of the term in print. (Another Business Week article in the 1970's referred to IBM as a "big blue chip company", but that didn't quite qualify as a legitimate "big blue" reference).
http://answers.google.com/answers/threadview?id=246292

Answer 2

Company Called Big Blue

Answer 3

Well, I lived in San Jose and IBM had a huge presence there. I was told it was a combination of things, in their logo, big blue letters and their main frames (also known as "big iron") had a distinctive blue color to the cabinets. Personally, I always have thought it was the gun metal blue of the computer cabinets...

Answer 4

Because:

1. They are one of the largest companies in the world.
2. Their logo consists of big, blue letters.

Answer 5

I always thought it was because of the financial term "Blue Chip", i.e. a well established company. But according to Wikipedia nobody quite knows for sure how this nickname originated. The links below have more information....