The integral membrane protein is one of the types of membrane proteins that is part of the membrane. It is permanently anchored to the membrane. The peripheral membrane protein is another type of membrane proteins that are just attached temporarily to the integral proteins, and definitely to the lipid bilayer.
The major difference between these two membrane proteins is that the integral proteins are firmly parts of the while bilayer, while peripheral proteins are found on the outer or inner surface of the phospholipid bilayer. Integral proteins are referred to as intrinsic proteins, while peripheral proteins are referred to as extrinsic proteins.
Also, the integral proteins interact more with the lipid layer's hydrophobic core than the peripheral proteins do. The former serve as enzymes, channel proteins, and carrier proteins, while peripheral proteins serve as surface antigens and receptors. In conclusion, integral proteins take about 70 percent of the whole membrane proteins, while peripheral proteins take just 30 percent of them.