Comparing and Contrasting

Comparison in writing discusses elements that are similar, while contrast in writing discusses elements that are different.

To differ means to be different. To differentiate means to make (someone or something) different in some way. 

As adjectives the difference between distinctive and distinguished. is that distinctive is that serves to distinguish between things while distinguished is celebrated, well-known or eminent because of past achievements; prestigious

 alike is in the same manner, form, or degree; in common; equally while likewise is (manner) in a similar manner.

differential: of, showing, or depending on a difference; differing or varying according to circumstances or relevant factors.

"the differential achievements of boys and girls"

discrepancy: a lack of compatibility or similarity between two or more facts.

whereas means "while"

whereby means "by which" or "through which"