C3 plants are temperate plants that directly reduce CO2 in the chloroplast. These plants undergo the C3 cycle for carbon fixation. Whereas, the C4 plants have an increased concentration of CO2. Here, the RuBisCo acts as a carboxylase. Thus, photorespiration is not seen in C4 plants.
Examples of C3 plants – Wheat, oats, etc.
Examples of C4 plants – Sugarcane, Pineapple, etc.