There are many ways to categorize digital marketing, but here are some common categories:

1. Search Engine Optimization (SEO): This involves optimizing your website and its content to rank higher in search engine results pages (SERPs) for specific keywords.

2. Pay-Per-Click (PPC) Advertising: This involves placing ads on search engines or other websites and paying a fee each time one of your ads is clicked.

3. Social Media Marketing: This involves using social media platforms (such as Facebook, Instagram, and Twitter) to promote your brand, products, or services.

4. Email Marketing: This involves sending marketing messages to a list of subscribers via email.

5. Content Marketing: This involves creating and distributing valuable, relevant, and consistent content to attract and retain a clearly defined audience.

6. Influencer Marketing: This involves partnering with influencers (people with large followings on social media) to promote your products or services to their followers.

7. Affiliate Marketing: This involves promoting other people's products or services and earning a commission for each sale made through your referral.

8. Mobile Marketing: This involves using mobile devices and platforms to promote your products or services.

9. Video Marketing: This involves using video to promote your products or services, or to entertain and engage your audience.

10. Local SEO: This involves optimizing your online presence to rank higher in search engine results pages for specific local keywords.