There are many compounds in organic chemistry containing carbonyl group as the part of their structure.
First kind of compounds with carbonyl group are carbonyl compounds (aldehyde with R-CHO and ketone, RCOR' as their structural formula)
Next, Carboxylic acid and their derivatives
Carboxylic acid: RCOOH
Ester: RCOOR'
Acid chloride: RCOCl
Anhydride: (RCO)2O
Amide: RCONH2
And carbohydrates, amino acids also have Carbonyl group in their structures.
Structure of carbonyl group: -C=O