Fats are lipids usually solid at room temperature, it contain more saturated fats. Generally, as chain becomes longer or gets more saturated, the triglyceride (ester derived from glycerol and three fatty acids) is more likely to be a fat.
Oils are liquid at room temperature. Most oils are less saturated fats and more unsaturated fats. Generally, as chains become shorter or more unsaturated, the triglyceride is more likely to be an oil.