Velma is frequently referred to as the smartest member of the gang, as well as the smartest student at Crystal Cove High. She strongly believes in finding proof and evidence before determining something is real. Velma is very knowledgeable when it comes to computers and research. However, she is also bossy, clingy, rude and demanding, as evidenced when she was dating Shaggy, forcing him to change who he was, and wanted him to choose her over Scooby. She didn't even seem to care when Scooby got framed and sent to jail and was glad to have Shaggy all to herself.
She also seems to be the most scheming and secretive member of Mystery Inc., as illustrated by her posing as the mysterious masked figure, and keeping a number of secrets from her friends, including the true identity of Angel Dynamite, and working for Mr. E when the gang briefly broke up.
She is implied to be Jewish: she listens to Klezmer music, and frequently exclaims "Oy" and "Oy gevalt". https://scoobydoo.fandom.com/wiki/Velma_Dinkley_(Scooby-Doo!_Mystery_Incorporated)