A picture clause is used in many programming environments to let the user change how text is printed or displayed. To change a picture clause, the user has to enter characters that have different effects, such as adding letters or formatting an area of the text. Some characters are used to increase font size or imply other characters, so these control characters may not be displayed in the actual text. Most programs normally do this automatically, so users typically will avoid having to set up the picture clause manually, but there are advantages to manually parsing the text.
Many programming languages and environments enable users to set up the basic elements behind a text document through the picture clause. Depending on how the file is parsed, this may affect a printed document, displayed text or both. This typically is coupled with forms that must be printed or displayed in a certain way, or specific documents that must have a certain formatting for them to be properly used.
As with most programming languages, characters are used to control the picture clause, but the characters used in this clause often are less extensive than those in other languages. Tags and attributes normally are required, but the control characters used in the clause often are just a single symbol or a letter. Each character has a different effect, but they typically push text, add letters or spaces, and add symbols into the text, such as for currency.
Some of the characters in a picture clause are meant to be displayed, such as characters that add symbols, numbers or text to the text file before it is printed or displayed. At the same time, there are many characters that are not displayed because their effects work on different elements of the document. For example, a character that enables the user to change the font size will not show up, but it still will enable the user to change the entire document.
While the picture clause is used often, most people will never see it being used. This is because the characters and programming often are working behind the scenes and affect most common text editor and form programs. At the same time, programmers are able to create their own clauses so they can set up custom documents. Aside from making a custom document, a programmer may use this to build an entire text program or the clause can be used to protect displayed text by preventing it from being printed.