What are the differences between an 11-30 and an 11-34 cassette in terms of gear ratios and performance?

An 11-30 cassette has smaller gear ratiOS compared to an 11-34 cassette, meaning it provides slightly easier pedaling at the expense of top speed. The 11-34 cassette offers a wider range of gear options, making it better for climbing steep hills but potentially sacrificing some efficiency on flat terrain.