Open 1 file

1 files: what are they and how do I open them?

1 file icon Are you facing difficulties opening unknown files on your computer, or wondering exactly what this file is?
We've got the information and best software solutions for opening these files effortlessly.

.1 file type #1: Manual page (Unix)

Documents with a .1 file extension are typically found on the Unix platform and are used in certain document systems in the manual / help file system.

Further details:

The "1" in Unix or Linux refers to the section number of the manual. The manual is divided into several sections, each for a different type of command or function.

Section 1 of the manual typically contains general commands that a user can use on the command line. So, a "1 file" in Unix would refer to a file that contains an unformatted manual page from section 1 of the Unix manual. This would typically be a text file that provides information on how to use a specific command.

Open file with:

Unix icon


A multi-tasking operating system for various platforms

GNU Emacs icon

GNU Emacs

A popular text editor for linux

Linux operating systems icon

Linux operating systems

A free open source operating system based on UNIX

FreeBSD icon


A Unix based operating system

NetBSD icon


A unix-derivate operating system

Solaris icon


A Unix certified operating system for workstations and servers

Sublime Text icon

Sublime Text

A sophisticated source code editor for programmers

Sublime Text for Mac icon

Sublime Text for Mac

A sophisticated Mac source code editor for programmers

Sublime Text for Linux icon

Sublime Text for Linux

A sophisticated Linux source code editor for programmers

macOS icon


A Unix-based desktop operating system for Apple Mac computers

.1 file type #2: AIM AOL IM file

Files with 1 extension are associated with AIM OL Instant Messenger and they are used as one of the internal various data files.

Further details:

The 1 file extension is used by AIM AOL Instant Messenger instant messaging client. The .1 file contains various data used for internal purposes of the AIM instant messenger. Similar files can be numbered from .1 to .999.

Open file with:

AOL Instant Messenger (AIM) icon

AOL Instant Messenger (AIM)

An instant messaging and presence computer program

.1 file type #3: Log file used by GNU Screen, a terminal multiplexer; records all output and input from a session for later review or analysis

A 1 file extension is related to the GNU Screen software. A 1 file contains log.

Further details:

The 1 file extension is associated with the Screen full-screen window manager that multiplexes a physical terminal between several processes.

The .1 file contains saved log data with information about running processes.

Open file with:


A full-screen window manager for Windows

.1 file type #4: Cache used by Google Android

Files with 1 file extension are related to the Google Android, an operating system for smart phones and tablets. A 1 file contains cache.

Further details:

The 1 file extension is associated with the Google Android, an operating system for smart phones, tablets and other smart devices.

The 1 file stores cached data used by system, or Android apps.

Open file with:

Google Android icon

Google Android

Popular OS for mobile devices

.1 file type #5: Binary data used by Inno Setup for installation purposes

Files with 1 file extension can also be found as installation resource packs for program setups made using Inno Setup software.

Further details:

The 1 file extension is associated with the Inno Setup, a free application used to create Windows application installation packages. The .1 file contains binary data used in an installation process of an application.

Open file with:

Inno Setup icon

Inno Setup

A freeware installation creator for Windows

.1 file type #6: Mozilla Firefox file

Files with 1 extension are always used by Mozilla Firefox to store data for cookies.

Further details:

File extension 1 is associated with the Mozilla Firefox and Netscape Navigator web browsers.

This type of .1 files is used for cookie, image, popup permissions files. It is used in earlier versions of these browsers.

Open file with:

Firefox icon


A popular free web browser from Mozilla

Netscape Navigator icon

Netscape Navigator

Older multi-platform web browser

.1 file type #7: Backup file for Pro/ENGINEER software

Files with 1 suffix can also be found as part of old Pro/ENGINEER 3D CAD software. Some sort of auto-recovery backup.

Further details:

File extension 1 is also associated with the Pro/ENGINEER (Creo Elements/Pro) 3D CAD/CAM/CAE modeling software.

A .1 file contains backup of Pro/ENGINEER data used as a prevent against computer crash.

Open file with:

Pro/Engineer (Creo Elements/Pro) icon

Pro/Engineer (Creo Elements/Pro)

Set of 3D CAD/CAM/CAE design tools from PTC

.1 file type #8: Archive files compressed with Stuffit software

A 1 file extension is associated with the Stuffit and used for its archive files.

Further details:

The 1 file extension is associated with the Stuffit compression utility for Mac and Windows also older versions are available for Linux and Solaris.

The 1 file contains the first part of Stuffit split archive.

Open file with:

Stuffit icon


A popular file archiving utility

StuffIt for Mac icon

StuffIt for Mac

Mac version of the popular utility

StuffIt Deluxe icon

StuffIt Deluxe

A commercial compression utility

StuffIt Deluxe for Mac icon

StuffIt Deluxe for Mac

A backup and archive utility

StuffIt Expander icon

StuffIt Expander

A free decompression utility with good file format support

StuffIt Expander for Mac icon

StuffIt Expander for Mac

A Mac version of the popular decompression utility

.1 file type #9: SNES split ROM image

Files with .1 file extension can also be found as Super Nintendo ROM cartridge images for SNES emulators like Snes.9x

Further details:

The 1 file extension is associated with the Super Nintendo ROM image file format used by various SNES emulators such as Snes9x.

This type of .1 files contains the first part of the split ROM image. To open split ROM you need to have all parts of it.

Open file with:

Snes9x icon


A free Super Nintendo emulator

What is the meaning of a file extension?

File extensions are characters that appear after the dot in a computer file's name. For example, the file "unknown-file.1" has the file extension "1". This is used to identify which program should open the file or what file type it is.
File extensions help you organize and manage files. They provide a quick and easy way to identify and associate the file type with the appropriate software.

We can help you open your file

In our database, we have collected a huge number of different file extensions, detailed descriptions, and programs that can be used to open or otherwise work with the file extensions listed in our database.
This database is an invaluable resource for users who want to understand better file extensions and what they can do with them. It also allows users to know different file types with the same purpose.

Only verified software links are provided

We have verified every software listed in our database. The software listed in our database includes links to the developer's or software's website. These links should allow you to download the right program for each file type. Using verified software from reputable sources helps minimize the risk of malware and viruses infecting your computer.