IBM research center founded by Thomas J. Watson, Sr., a former IBM chairman in 1961.
It is located in Westchester County, New York and is part of the Thomas J. Watson Research Center, the largest research facility of the IBM Research Division.

It is said, that is was founded primarily as a means to avoid technological surprises and only secondary as a leading research center.

... an anecdote from IBM's Yorktown Heights Research Center.  When a
programmer used his new computer terminal, all was fine when he was sitting
down, but he couldn't log in to the system when he was standing up.  That
behavior was 100 percent repeatable: he could always log in when sitting and
never when standing.

Most of us just sit back and marvel at such a story; how could that terminal
know whether the poor guy was sitting or standing?  Good debuggers, though,
know that there has to be a reason.  Electrical theories are the easiest to
hypothesize: was there a loose wire under the carpet, or problems with static
electricity?  But electrical problems are rarely consistently reproducible.
An alert IBMer finally noticed that the problem was in the terminal's keyboard:
the tops of two keys were switched.  When the programmer was seated he was a
touch typist and the problem went unnoticed, but when he stood he was led
astray by hunting and pecking.
        -- "Programming Pearls" column, by Jon Bentley in CACM February 1985