fromEnglish Grammar Today
We use the conjunctionwhereasto indicate a contrast between two facts or ideas:
He loves foreign holidays,whereashis wife prefers to stay at home.
Whereasmost new PCs have several USB slots, older ones often only had one.
Warning:
Whereasmeans the same aswhilein sentences expressing contrasts. It does not mean the same aswhilewhenwhilerefers to time:
The south has a hot, dry climate,whereas/whilethe north has a milder, wetter climate.
The secretary took care of my appointmentswhileI was away from the office.
Not: …whereas I was away from the office.
See also:
Whileandwhilst