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@@ -9,7 +9,7 @@ Much of computer science was pioneered in the latter half of the 20th century.
 
 Students who are interested in computer science will first learn about both hardware and software. It is important to learn how computers work at a low level of abstraction (machine language) and at a high level of abstraction (modern scripting languages like JavaScript) because it will help individuals understand computer science intuitively. 
 
-In 21st century, computer science has become a backbone for every technological leap we take forward.
+In the 21st century, computer science has become a backbone for every technological leap we take forward.
 
 # Computer Science Fields
 Computer science is categorized into several fields. The following are among the current established and well-studied fields. Most of the fields are further categorized into subfields.