1. Key Difference 1: Monetization Model Google AdSense uses a cost-per-click (CPC) model to monetize websites, where publishers earn revenue when visitors click on the ads displayed on their sites. On the other hand, Twitter Ads primarily uses a cost-per-engagement (CPE) model, where advertisers pay when users engage with their ads by liking, retweeting, or replying to them.

2. Key Difference 2: Targeting Options Google AdSense provides a wide range of targeting options to advertisers, including contextual targeting (based on website content), demographic targeting (based on user characteristics), and interest targeting (based on user interests). In contrast, Twitter Ads offers more granular targeting options, allowing advertisers to target users based on keywords, interest categories, follower look-alikes, and tailored audiences.

3. Key Difference 3: Ad Formats Google AdSense supports various ad formats, such as text ads, display ads, video ads, and native ads, providing flexibility for advertisers to choose the most suitable format for their campaigns. In comparison, Twitter Ads primarily focuses on native ads, which seamlessly blend into the Twitter feed, ensuring a non-disruptive user experience.

4. Key Difference 4: Ad Placement Google AdSense gives publishers control over the placement of ads on their websites, allowing them to optimize the position and design of the ads to maximize user engagement. In contrast, Twitter Ads places ads within users' Twitter feeds, interspersed with organic content, ensuring ads appear organically in users' timelines.

5. Key Difference 5: Audience Reach Google AdSense has a vast network of publishers, reaching a broad audience across different websites and platforms. On the other hand, Twitter Ads allows advertisers to reach Twitter's active user base, which consists of millions of monthly active users, providing an opportunity to target a specific social media-savvy audience.

6. Key Difference 6: Campaign Objectives Google AdSense primarily focuses on driving website traffic and generating clicks for advertisers' websites. In contrast, Twitter Ads offers a broader range of campaign objectives, including increasing brand awareness, driving app installs, promoting video views, and encouraging website conversions.

In Summary, Google AdSense and Twitter Ads differ in their monetization model, targeting options, ad formats, ad placement, audience reach, and campaign objectives.