Spread spectrum. In telecommunication and radio communication, spread-spectrum techniques are methods by which a signal (e.g., an electrical, electromagnetic, or acoustic signal) generated with a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth.
Lipids are one of the four major groups of organic molecules; the other three being proteins, nucleic acids (DNA), and carbohydrates (sugars). Lipids are made up of the same elements as carbohydrates: carbon, hydrogen, and oxygen.
Fats are just one type of lipid, a category of molecules united by their inability to mix well with water. Lipids tend to be hydrophobic, nonpolar, and made up mostly of hydrocarbon chains, though there are some variations on this, which we'll explore below.