As you can see from the image below, phospholipid molecules contain two main parts: a hydrophilic head and hydrophobic tail. The root word hydro refers to water. The root word -phil means loving or attracted and the root word -ic means the word is an adjective.
The root word -phob means “fear of.”
The hydrophilic head contains one or more charges that are attracted to the partial charges of water. (In other words, it is water-soluble.)
The hydrophobic tails are made of fatty acids, which contain no charges and therefore are not attracted to water. (In other words, the fatty acid tails are fat-soluble.)
In cells, phospholipid molecules are one of the molecules found in the membranes. The plasma membrane surrounds the cell but there are also membrane-bound organelles (e.g., mitochondria, Golgi complex, etc.).
As you can see from the figure above, the hydrophilic heads are attracted to the water that is found inside and outside of the cell.