Editing World file (section)

==Filename extension==
The base [[filename]] of a world file matches the raster's base filename, but has a different [[filename extension]] (suffix). There are three [[filename extension]] naming conventions used for world files, with variable support across software.

One simple convention with widespread support is to append the letter "w" to the end of the raster filename. For example, a raster named {{mono|''mymap''.jpg}} should have a world file named {{mono|''mymap''.jpgw}}.

An alternative file naming convention that uses a three-character extension to conform to the [[8.3 filename|8.3 file naming]] convention uses the first and last character of the raster file's extension, followed by "w" at the end. For example, here are a few naming conventions for popular raster formats:
{| class="wikitable"
! Raster format !! Raster file name !! World file name
|-
| [[GIF]] || {{mono|''mymap''.gif}} || {{mono|''mymap''.gfw}}
|-
| [[JPEG]] || {{mono|''mymap''.jpg}} || {{mono|''mymap''.jgw}}
|-
| [[JPEG 2000]] || {{mono|''mymap''.jp2}} || {{mono|''mymap''.j2w}}
|-
| [[Portable Network Graphics|PNG]] || {{mono|''mymap''.png}} || {{mono|''mymap''.pgw}}
|-
| [[TIFF]] || {{mono|''mymap''.tif}} || {{mono|''mymap''.tfw}}
|}

A third convention is to use a {{mono|.wld}} file extension, irrespective of the type of raster file, as supported by [[GDAL]] and [[QGIS]], but not [[Esri]].{{efn |name="Esri wld" |Esri also has another ''world file'' format that applies to computer-aided design or [[Computer-aided design|CAD]] drawing files.  That standard refers to the format of plain text computer files with names ending in {{mono|.wld}} and is not discussed in this article.}}