Step 1 : Introduction to the question "What is the best selling novel of all time?"
...With over 500 million copies sold, Don Quixote is the best-selling novel of all time. In this incredibly popular Spanish epic, Don Quixote has become so entranced by reading romances of chivalry that he determines to become a knight errant and pursue bold adventures, accompanied by his squire, the cunning Sancho Panza. The book is considered one of the most influential pieces of Spanish literature of the Spanish Golden Age. The novel remains incredibly popular, too. In 2005 -- the 400th anniversary of the novel -- a Spanish-language version of "Don Quixote" sold more than 600,000 copies in just two months.
Step 2 : Answer to the question "What is the best selling novel of all time?"
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