The File Information Database

Search over 10,000 file extensions and software programs.

File Type of the Day

Today • June 21


Valve Data File

A VDF file is a data file format used by Valve's Source game engine. It contains various kinds of game metadata, including data for resources, installation scripts, configuration scripts, and visualization elements.

June 20


Java Class File

A CLASS file is a compiled .JAVA file created by the Java compiler. It contains bytecode, which is binary program code that is executable when run by a Java Virtual Machine (JVM).

June 19


Objective-C Implementation File

An M file is a class implementation file used by programs written in Objective-C. It begins with the @implementation directive and initializes variables and functions that can be referenced by other Objective-C source files.

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