some useful English

unixnovice

RDBMS=relational database management system
IDS= intrusion detection system
SQL=structured query language
#alpha# :indicates that the release contains some large section of new code that hasn't been 100% tested
#beta#:means that all new code has been tested. No major new features that could cause corruption in old code are added
#gamma#: is a beta that has been around a while and seems to work fine,and  this is the main release type.
#man page:
Discussion
Linux sees all the man pages on a system as part of a single manual. This manual is divided into sections:
1 Executable programs or shell commands
2 System calls
3 Library calls
4 Special files (usually found in /dev)
5 File formats and conventions
6 Games
7 Miscellaneous
8 System administration commands
9 Nonstandard kernel routines
n New documentation, which may be moved later
l Local documentation, specific to your system

#
about /etc/passwd
:if the  second colon-separated field(passwd store place) in echo entry in it contains an X,system using the shadow.at other case system use passwd.
#disable a user:
usermod -l username  this cmd same as (exclamation mark! at the passwd entry head)
#LDAP :the Lightweight Directory Access protocol
#NIS:  the Network Information Service
如果出现图标无图片:可以删C:\Documents and Settings\user\Local Settings\Application Data\IconCache.db

本文来自ChinaUnix博客，如果查看原文请点：http://blog.chinaunix.net/u/23271/showart_161956.html