How do government corporations differ from other corporations in the united states

I think the difference can be based on ownership. A government corporation is owned by the nation while a private company comes from stockholders. 

Another difference between the two is profit. The shares of stocks determine the division of profit in a private corporation. Profits in a government corporation shall become earnings for expenditures.
These are just some main points of comparison. Employment, different systems, and management are other facts that can also be used for comparison. 

A) the gas is compressed