Drop-in replacement is a term used in computer science and other fields. It refers to the ability to replace one hardware or software component with another, without any other code or configuration changes being required and resulting in no negative impacts. Usually, the replacement has some benefits including one or more of the following:

• increased security
• increased speed
• increased feature set
• increased compatibility (e.g. with other components or standards support)
• increased support (e.g. the old component may no longer be supported, maintained, or manufactured)

• Pin compatibility
• Plug compatible
• Clone (computing)
• Backward compatibility
• Kludge