The main types of digital marketing include search engine optimization (SEO), pay-per-click advertising (PPC), social media marketing, content marketing, email marketing, influencer marketing, and affiliate marketing.

Social media plays a key role in digital marketing by providing a platform for brands to interact with their target audience, build relationships, and share content. Social media can also be used for paid advertising, influencer marketing, and customer service.

Email marketing allows brands to reach their target audience directly, with personalized and relevant messages. It can help generate leads, increase conversions, build brand loyalty, and drive repeat sales.

The success of a digital marketing campaign can be measured through various metrics, including website traffic, conversions, lead generation, sales, and customer engagement. Tools such as Google Analytics, social media analytics, and email marketing software can help track and analyze these metrics.

Content marketing is a strategic approach to digital marketing that focuses on creating and distributing valuable, relevant, and engaging content to attract and retain a clearly-defined audience — and, ultimately, to drive profitable customer action.

Paid advertising, also known as pay-per-click (PPC) advertising, allows brands to reach their target audience through online advertising platforms, such as Google Ads and Facebook Ads. Paid advertising can be an effective way to drive immediate traffic and generate leads, but it should be part of a broader, integrated digital marketing strategy.

Staying up-to-date with the latest digital marketing trends and technologies requires ongoing education and professional development, reading industry blogs and publications, attending conferences and events, and networking with other professionals in the field.