File extension Details of HLB, HEX, HM3, HMX, HGL, VFS, ULS, CTG, CHK

Name:	HLB
File Type:	VMS / VAX Help Library
Popularity:	1
Category:	misc
File Description:	Library of help documentation for a VMS / VAX system
Open Programs:	Windows HP OpenVMS View in a text editor

Name:	HEX
File Type:	Hexadecimal Source File   (Most common)
Popularity:	3
Category:	misc
File Description:	Contains settings, configuration information, or other data saved in a hexadecimal format; may be stored in either a binary or text format. NOTE: Binary hex files can only be opened with hex-editing programs; text-based hex files can be opened and edited with a text editor.
Open Programs:	Mac OS HexEdit HexEditor Windows Heaventools FlexHex Hex Workshop Hex Editor Cygnus Hex Editor HHD Hex Editor

Name:	HM3
File Type:	Help & Manual 3 Project
Popularity:	3
Category:	misc
File Description:	Windows help documentation created by Help & Manual authoring tool; formatted as RTF files; can be exported to several different formats including Winhelp
Open Programs:	Windows EC Software Help and Manual

Name:	HMX
File Type:	Help & Manual 4 Project
Popularity:	3
Category:	misc
File Description:	Windows help documentation created by Help & Manual authoring tool; formatted as XML files; can be output to HTML Help, Cross-platform Help, PDF, Visual Studio Help, Winhelp, Word documents, e-Books, or Print manuals
Open Programs:	Windows EC Software Help and Manual 4 or later

Name:	HGL
File Type:	HP Graphics Language File
Popularity:	3
Category:	misc
File Description:	Printer control language developed by Hewlett-Packard (often referred to as HPGL); used by plotters from HP and other manufacturers, which print images using lines instead of dots. Most HGL files contain a few lines of setup commands, followed by a list of printing commands; the printing commands instruct the plotter what to draw on the page. HPGL files often have a .HPGL extension.
Open Programs:	Windows Software Companions ViewCompanion Pro Corel Paint Shop Pro

Name:	VFS
File Type:	Virtual File System Index
Popularity:	3
Category:	misc
File Description:	Contains an index of directories and files stored on a hard drive or other media device; may be used to create a virtual file system, which speeds up browsing and searching for files. NOTE: HP All-in-One printers may add a VFS file to memory cards inserted into the card slot; this happens when the "Faster Browsing" option is turned on; to prevent VFS files from being created on memory cards, press "Setup" on the printer, then select "Preferences," then choose "Enable Faster Browsing" and select "OFF."
Open Programs:	Mac OS Used by various hardware devices Not meant to be opened manually Windows Used by various hardware devices Not meant to be opened manually

Name:	ULS
File Type:	NetMeeting User Location Service File
Popularity:	3
Category:	misc
File Description:	Contains information about an Internet location; used by Microsoft NetMeeting to connect users to each other; the Internet Locator Server (ILS) sends a file called "Ulserver.uls" to clients with IP address and port information. NetMeeting was part of Windows XP, but is not included with Windows Vista; it has been replaced by Windows Meeting Space and Microsoft Office Live Meeting.
Open Programs:	Windows Microsoft NetMeeting

Name:	CTG
File Type:	Canon Digital Camera Catalog File
Popularity:	3
Category:	misc
File Description:	Catalog index file created on Canon digital cameras; stored in the CANONMSC folder and corresponds to other folders saved on the memory card; i.e. "382.CTG" contains information about images in the folder "382CANON." CTG files contain information about the number of images stored in each folder on the memory card (typically up to 99); they should not be manually opened or edited by the user; the camera will automatically delete the CTG files when the corresponding images are erased. CTG files are much smaller than .JPG files and do not contain any image data; therefore they cannot be converted to JPEG files.
Open Programs:	Mac OS Not meant to be opened Windows Not meant to be opened

Name:	CHK
File Type:	Saved File Fragment   (Most common)
Popularity:	3
Category:	misc
File Description:	Windows file fragment cleaned from the hard disk by ScanDisk or CHKDISK; stored in the FOUND folder after a disk scan has been performed. CHK files typically can be deleted since the information has been moved somewhere else on the disk; however, file contents may be checked with CHK-Mate before being removed.
Open Programs:	Windows DIY DataRecovery CHK-Mate (examines the contents of CHK files) UnCHK or FileCHK (recovers data from a CHK file)

Name:	CA
File Type:	Initial Telnet Cache
Popularity:	1
Category:	misc
File Description:	Stores information used for establishing telnet connections; typically found on Unix/Linux platforms, which include a terminal interface. The file "named.ca" contains a list of the world's root DNS servers.
Open Programs:	Linux Typically should not be opened May be viewed with a text editor