This is a formal document used to describe in detail for software developers a product's intended capabilities, appearance, and interactions with users.

Functional specification

Explanation:

Functional specification is a formal statement, more like a contract between a software developer and an employer on what he (the developer) should do. the document is use to describe in detail for the developers what a product is suppose to do, how the user interface of the product should look like, how it should interact with users and much more.

do not use any of these common illegal characters/symbols:

# pound

% percent

& ampersand

{ left curly bracket

} right curly bracket

\ back slash

< left angle bracket

> right angle bracket

* asterisk

? question mark

/ forward slash

  blank spaces

$ dollar sign

! exclamation point

' single quotes

" double quotes

: colon

@ at sign