Incorrect spelling will change the meaning of a sentence that you write so much has changed, such as "bear" and "bare" this two words pronounced the same, but the "bare" means "naked bare bear" section which means bear.
Spelling errors will change the meaning of a sentence you wrote is changed to something more like "bare" and "bear" two words are pronounced the same, but "bare" means that bare the "bear" means that the bears.
The spelling wrong will change the meaning of the sentence you write that change dramatically, such as "bare" and "bear" two words sound alike. But "bare" means no nude. "Bear" means bear.