These two spellings [cannot/can not] are largely interchangeable, but by far the most common is “cannot” and you should probably use it except when you want to be emphatic: “No, you can not wash the dog in the Maytag.” There's no difference in meaning between cannot and can not.

Why Cannot can t?

Here is a quick summary: Can't is a contraction of cannot, and it's best suited for informal writing. In formal writing and where contractions are frowned upon, use cannot. It is possible to write can not, but you generally find it only as part of some other construction, such as “not only . . . but also.”

IS can not correct?

Both cannot and can not are acceptable spellings, but the first is much more usual. You would use can not when the "not" forms part of another construction such as "not only." For example: These green industries can not only create more jobs, but also promote sustainable development of the land. Back to Usage.