‘Into’ and ‘in to’ contain the same letters; however, the words are different parts of speech that are used in different contexts and spelled differently.
‘Into’ is a preposition. It is generally within prepositional phrases that contain the object to which the preposition refers as well as any object-modifying words. Any phrase that uses ‘into’ is essentially an adverbial phrase. These phrases modify the preceding verbs or phrases. Using ‘in to’ where ‘into’ is necessary can create confusion because it changes the meaning of the sentence and misrepresents what you are trying to say. Consider the following examples:
Incorrect: When you want to grow in to experience that aids in your success as a freelance writer, employ the right resources. (Here, the implied meaning is that you want to grow in – as in inward in order to experience – which does not make sense).
Correct: To grow into a successful freelance writer, you must engage in effective time management. (In this sentence, the meaning is that you want the ability to become a successful freelance writer – which makes perfect sense).
‘In to’ is both an adverb and a preposition. ‘In’ is the adverb; ‘to’ is the preposition. When these two words are used together, the adverb modifies the verb to which it applies, and the preposition has an object of its own. The meaning implies you are taking something and moving it, handing it or turning it ‘in’ for example to the object connected with ‘to,’ or the preposition. Confusing the use of “in to” with ‘into’ can create confusion as well.
Incorrect: She went to turn into the driveway. (Here the implication is that “she” literally morphed into the driveway – which is both confusing and impossible).
Correct: As he drove down the street, he almost missed where he needed to turn in to the parking lot. (‘In’ is the adverb that modifies ‘turn,’ and ‘to’ is a preposition that takes ‘the parking lot’ as its object).
Learn the difference between “into” versus ‘in to’ to ensure you always convey the proper meaning to avoid confusing your readers.