/

Root of the overall file-system name space 

/dev

Primary location for special files 

/dev/dsk

Block disk devices 

/dev/rdsk

Raw disk devices 

/dev/pts

Pseudo terminal slave devices 

/dev/rmt

Raw tape devices 

/dev/sad

Entry points for the STREAMS Administrative Driver  

/dev/term

Terminal devices 

/etc

Host-specific system administrative configuration files and databases 

/etc/acct

Accounting system configuration information 

/etc/cron.d

Configuration information and FIFO for cron

/etc/default

Default information for various programs 

/etc/dfs

Configuration information for exported file systems 

/etc/fs

Binaries organized by file-system types for operations required before /usr is mounted

/etc/inet

Configuration files for Internet services 

/etc/init.d

Scripts for transitioning among run levels 

/etc/lib

Shared libraries needed during booting 

/etc/lp

Configuration information for the printer subsystem 

/etc/mail

Mail subsystem configuration 

/etc/net

Configuration information for ti (transport independent) network services

/etc/opt

Configuration information for optional packages 

/etc/rc0.d

Scripts for entering or leaving run level 0 

/etc/rc1.d

Scripts for entering or leaving run level 1 

/etc/rc2.d

Scripts for entering or leaving run level 2 

/etc/rc3.d

Scripts for entering or leaving run level 3 

/etc/rcS.d

Scripts for entering or leaving run level S 

/etc/saf

Service Access Facility (SAF) files, including FIFOs 

/etc/skel

Default profile scripts for new user accounts 

/etc/sm

Status monitor information 

/etc/sm.bak

Backup copy of status monitor information 

/etc/tm

Trademark files; contents displayed at boot time 

/etc/uucp

Configuration information for uucp

/export

Default root of the exported file-system tree 

/home

Default root of a subtree for user directories 

/kernel

Subtree of loadable kernel modules, including the base kernel itself as /kernel/unix

/mnt

Temporary mount point for file systems 

/opt

Root of a subtree for add-on application packages 

/opt/SUNWspro

Mount/installation point for unbundled language products 

/platform

Subtree of loadable kernel modules 

/sbin

Essential executables used in the booting process and in manual system failure recovery 

/tmp

Temporary files; cleared during boot sequence 

/usr

Mount point for the /usr file system

/var

Root of a subtree of various files 

/var/adm

System logging and accounting files 

/var/crash

Default depository for kernel crash dumps 

/var/cron

Log file for cron

/var/lp

Line printer subsystem logging information 

/var/mail

Directory where users' mail is kept 

/var/news

Community service messages (not to be confused with USENET-style news) 

/var/nis

NIS+ databases 

/var/opt

Root of a subtree for various files associated with optional software packages 

/var/options

Provides package compatibility with pre-SunOS 5.0 packages 

/var/preserve

Backup files for vi and ex editors

/var/sadm

Databases maintained by the software package management utilities 

/var/saf

System Access Facility (SAF) logging and accounting files 

/var/spool

Directories for spooled temporary files 

/var/spool/cron

Spool files for cron and at

/var/spool/locks

Spooling lock files 

/var/spool/lp

Line printer spool files 

/var/spool/mqueue

Mail queued for delivery 

/var/spool/pkg

Spooled packages 

/var/spool/uucp

Queued uucp jobs

/var/spool/uucppublic

Files deposited by uucp

/var/tmp

Directory for temporary files not cleared during boot sequence 

/var/uucp

Log and status files for uucp

/var/yp

Databases for yp (for backward compatibility with NIS and ypbind)

/usr/4lib

Libraries for the binary compatibility a.out package (BCP)

/usr/bin

Location for standard system commands 

/usr/bin/sunview1

SunView executables, part of BCP 

/usr/ccs

The C compilation system 

/usr/ccs/bin

Binaries 

/usr/ccs/lib

Libraries and auxiliary files 

/usr/demo

Demo programs and data 

/usr/games

Game binaries and data 

/usr/include

Include header files (for C programs, and the like) 

/usr/kernel

Additional modules 

/usr/kvm

Implementation architecture-specific binaries and libraries 

/usr/lib

Various program libraries, architecture-dependent databases, and binaries not invoked directly by the user 

/usr/lib/acct

Accounting scripts and binaries 

/usr/lib/dict

Database files for the spell command

/usr/lib/class

Scheduling class-specific directories containing executables for priocntl and dispadmin commands

/usr/lib/font

Font description files for troff

/usr/lib/fs

File system type dependent modules; not invoked directly by the user 

/usr/lib/iconv

Conversion tables for iconv

/usr/lib/libp

Profiled libraries 

/usr/lib/locale

Internationalization and localization databases 

/usr/lib/localedef

Locale source file for localedef.

/usr/lib/lp

Line printer subsystem databases and back-end executables 

/usr/lib/mail

Auxiliary programs for the mail subsystem 

/usr/lib/netsvc

Internet network services 

/usr/lib/nfs

Auxiliary NFS-related programs and daemons 

/usr/lib/pics

PIC archives needed to build the runtime linker 

/usr/lib/refer

Preprocessor for nroff/troff

/usr/lib/sa

Scripts and commands for the system activity report package  

/usr/lib/saf

Auxiliary programs and daemons related to the Service Access Facility (SAF) 

/usr/lib/spell

Auxiliary spell-related programs and databases

/usr/lib/uucp

Auxiliary uucp-related programs and daemons

/usr/local

Commands local to a site 

/usr/net/servers

Entry points for foreign name-service requests related by the listener 

/usr/oasys

Files pertaining to the optional FACE package 

/usr/old

Programs that are being phased out 

/usr/openwin

Mount or installation point for OpenWindows software 

/usr/sadm

Various files and directories related to system administration 

/usr/sadm/bin

Binaries for use by FMLI scripts 

/usr/sadm/install

Executables and scripts for package management 

/usr/sbin

Executables for system administration 

/usr/sbin/static

Statically linked versions of selected programs from /usr/bin and /usr/sbin; used to recover from broken dynamic linking

/usr/share

Architecture-independent databases 

/usr/share/lib

Architecture-independent databases 

/usr/share/lib/keytables

Keyboard layout description tables 

/usr/share/lib/mailx

Help files for mailx

/usr/share/lib/nterm

Terminal tables for nroff

/usr/share/lib/pub

Various data files 

/usr/share/lib/spell

Auxiliary spell-related databases and scripts

/usr/share/lib/tabset

Tab-setting escape sequences 

/usr/share/lib/terminfo

Terminal description files  

/usr/share/lib/tmac

Macro packages for nroff and troff

/usr/share/lib/zoneinfo

Time zone information 

/usr/share/src

Source code for kernel, libraries, and utilities 

/usr/snadm

Files associated with Administration Tool (admintool)

/usr/ucb

Berkeley compatibility package binaries 

/usr/ucbinclude

Berkeley compatibility package header files 

/usr/ucblib

Berkeley compatibility package libraries 

/usr/vmsys

Files pertaining to the optional FACE package