kb/data/developer.mozilla.org/en-US/docs/Glossary/Parameter-0.md

title	chunk	source	category	tags	date_saved	instance
Parameter - Glossary | MDN	1/3	https://developer.mozilla.org/en-US/docs/Glossary/Parameter	reference	web, html, css, javascript, documentation	2026-05-05T05:39:56.177944+00:00	kb-cron

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1. Glossary
2. Parameter

Parameter

Parameters are named variables declared as part of a function. They are used to reference the arguments passed into the function. For example: There are two kinds of parameters:

input parameters

the most common kind; they pass values into functions. Depending on the programming language, input parameters can be passed in several ways (e.g., call-by-value, call-by-address, call-by-reference).

output/return parameters

primarily return multiple values from a function, but are not recommended since they cause confusion

In this article

• Parameters versus arguments
• See also

Parameters versus arguments

Note the difference between parameters and arguments :

• Function parameters are the names listed in the function's definition.
• Function arguments are the real values passed to the function.
• Parameters are initialized to the values of the arguments supplied.

See also

• Difference between parameters and arguments
• Function declaration
• Function expression
• Related glossary terms:
  • Function
  • Argument