The ai file extension is associated with Adobe Illustrator the well known vector graphics editor for the Macintosh and Windows platforms.

AI file format is a widely used format for the exchange of 2D objects. Basic files in this format are simple to write, but files created by applications implementing the full AI specification can be quite large and complex and may be too slow to render.

Simple .ai files are easy to construct, and a program can create files that can be read by any AI reader or can be printed on any PostScript printer software. Reading AI files is another matter entirely. Certain operations may be very difficult for a rendering application to implement or simulate. In light of this, developers often choose not to render the image from the PostScript-subset line data in the file. However almost all of the image can usually be reconstructed using simple operations.implementation of the PostScript language.

The ai files consist of a series of ASCII lines, which may be comments, data, commands, or combinations of commands and data. This data is based on the PDF language specification and older versions of Adobe Illustrator used format which is variant of Adobe Encapsulated PostScirpt (EPS) format.

If The EPS is a slightly limited subset of full PostScript, then Adobe Illustrator AI format is a strictly limited, highly simplified subset of EPS. While EPS can contain virtually any PS command that's not on the verboten list and can include elaborate program flow logic that determines what gets printed when, an AI file is limited to a much smaller number of drawing commands and it contains no programming logic at all. For all practical purposes, each unit of "code" in an AI file represents a drawing object. The program importing the AI reads each object in sequence, start to finish, no detours, no logical side-trips.

MIME types: application/postscript

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AI file extension - Open, view and convert .ai files