Portable Document Format (PDF) is a file format used to present and exchange documents reliably, independent of software, hardware, or operating system. Invented by Adobe, PDF is now an open standard maintained by the International Organization for Standardization (ISO).
ACCELA HEAT is a trademark and brand of Sears Brands, LLC. Filed to USPTO On Wednesday, October 01, 2014, The ACCELA HEAT covers Heat-regulating software, sold as an integral component of ovens for the purpose of baking food without the need to preheat the oven. Search for other trademarks at Trademarkia.
In this context, heat is the term we use to refer specifically to the transfer of thermal energy from one object or a system to another, transfer being the key. The thermal energy is the energy possessed within the object or within the system due to movement of particles. They're different - heat and thermal energy. You can feel the heat if you hold your hand above the stove.