SEO is the Search Engine Optimization, it includes :

• Keyword analysis and research
• Keyword strategy
• Competition Analysis
• Website modifications
• Link building
• Manual Submissions to search engines and directories
• Monthly ranking report
• Search Engine Submission
• Pay Per Click
• Web Site Optimization
• On Page Optimization
• Meta Tag Optimization
• Heading Tag Optimization
• Image Tag Optimization
• Content Optimization
• Off Page Optimization
• Link Building Services
• Anchor Text Optimization
• Article Writing & Submission
• On Site Optimization
• Ethical Search Engine Optimization
• Organic SEO
• SEO Glossary
• Dynamic Site Optimization

All this process are used for Site Promotion.