This report provides a comprehensive analysis of Apple Inc.'s marketing principles and brand extension strategy. It begins with an introduction and background of Apple Inc., detailing its founding and market share across various product categories such as computers, smartphones, tablets, smartwatches, and music services. The report examines Apple's existing brand value and its impressive growth, particularly in revenue. A key focus is on Apple's new product strategy, specifically the brand extension into smart footwear, leveraging the success of the Apple Watch series 6. The report further explores the proposed target market using the Segmentation, Targeting, and Positioning (STP) framework. It addresses key trends and PESTLE issues, highlighting the health-conscious consumer segment. A comparative analysis of the proposed brand extension with competitors is also provided. The report concludes by emphasizing the effectiveness of marketing principles in brand extension and its advantages for organizational growth and development. References from academic journals and online sources support the analysis.