What does the term unalienable mean? What are the three "unalienable rights" listed in the Declaration?

Unable to be taken away from or given away by the possessor. Life, Liberty and the pursuit of Happiness" is a well-known phrase in the United States Declaration of Independence. The phrase gives three examples of the "unalienable rights" which the Declaration says have been given to all human beings by their creator, and which governments are created to protect.