What is the difference between SEO and SEM

The difference between search engine optimization (SEO) and search engine marketing (SEM) is that SEO is focused on improving a website to increase visibility in unpaid search results, while SEM uses both SEO and paid ads (often called pay-per-click ads or PPC ads) to drive traffic from search engines.

Generally, SEO helps you earn organic (unpaid) traffic over time, and SEM is an umbrella approach that helps you drive both immediate traffic and long-term traffic.

When to use SEO vs. SEM:

• SEO: If you have the time and resources to create high-quality content and a strong website foundation, SEO earns you stable, long-term traffic at a lower ongoing cost
• SEM: If you have a budget for ads and also want to achieve the steady growth of SEO, SEM helps you quickly reach your audience and grow traffic over time

Further reading : SEO vs. SEM