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 ---
 title: Mainframe_computers
-tags: []
-created: Friday, September 27, 2024 
+tags: [computer-history]
+created: Friday, September 27, 2024
 ---
+
 # Mainframe_computers
 
+A mainframe computer, also known as a "big iron" is a high performance computer
+used for resource-intensive tasks that require greater security and availability
+than smaller scale machines. They are typically used for centralised rather than
+distributed computing.
 
+The heyday of mainframes was before the mini- and micro-computer revolution but
+they are still used.
 
-
+IBM remains the main manufacturer and service provider for mainframes. Example
+use cases include banks who need to process large volumes of transatction and
+high frequency tranding; government departments, the military and internal
+revenue who require huge databases.