The purpose of this study was to determine if the use of a graphical teaching and learning approach via the graphing calculator enhances students' understanding of the formal definition of limit. College students in six sections of Calculus I participated by completing a test prior to the introduction of the definition, and completing a second similar test after covering this topic. Students in four sections received traditional instruction on the formal definition of limit, but in two other sections an approach utilising graphing calculators was incorporated into the instruction for one and two days, respectively. Students who received the graphical instruction for two days performed significantly better on all but one of the conceptual items on the post-test, as compared to the students who received traditional instruction and with those who received the graphical instruction for only one day. (Contains 4 figures and 3 tables.)