Practical Guide for Linux16 - App Store

Best Seller UNIX/Linux Reference since 2010 for both students and working adults! Now, with updated content for 2026, Air Print and iOS Light and Dark modes.

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Making First Steps (passwd, su)
Logging Out, Shell (exit, Ctrl-d)
Special Characters (Ctrl-c, Ctrl-h, Ctrl-d)
Metacharacters (?, *, [])
Environment (env)
How To Change Environment Variables (.profile, .login)
Navigating The File System (absolute, relative paths)
How To Use Paths I (pwd, cd)
How To Use Paths II (cd ..)
Files and Directories - Part I (ls, ls -l)
Files and Directories - Part II(ls -al)
Files and Directories - Part III (ls -R)
Permissions - Part I (id)
Permissions - Part II (rwx-)
Permissions - Part III (how to read)
Permissions - Part IV (chmod)
Viewing Files (more, cat, head, tail)
Searching in Files - Part I (grep options)
Searching in Files - Part II (grep examples)
Renaming Files (mv)
Copying Files (cp)
Deleting Files (rm)
Links (ln)
Compare Files (diff)
Compare Directories (dircmp)
Creating Directories (mkdir)
Finding Files and Directories (find)
Create and Edit Files With vi - Part I
Create and Edit Files With vi - Part II (insert mode)
Create and Edit Files With vi - Part III (searching)
Create and Edit Files With vi - Part IV (editing)
Create and Edit Files With vi - Part V (deleting)
Create and Edit Files With vi - Part VI (saving)
Create and Edit Files With vi - Part VII (line-edit mode)
Printing Files (lp, lpr)
Archiving Files (tar)
Transferring Files Between Computers (nslookup, ping)
Telnet
FTP - Part I (connecting)
FTP - Part II (transferring files)
More UNIX Commands (uname, arch)
Date and Time (date, cal)
Find Out About Other Users - Part I (who)
Find Out About Other Users - Part II (finger)
History
Disk Space (df, du, gzip, gunzip)
Memory (free, uptime)
Processes (Jobs) - Part I (ps)
Processes (Jobs) - Part II (ps -ef, kill, fuser)
Processes (Jobs) - Part III (at)
Electronic Mail - Part I (elm)
Electronic Mail - Part II (command mode)
Advanced UNIX - Redirection Part I (> , > > )
Advanced UNIX - Redirection Part II (|)
Practical sed and awk - Part I (sed)
Practical sed and awk - Part II (sed example)
Practical sed and awk - Part III (sed example)
Practical sed and awk - Part IV (awk)
Practical sed and awk - Part V (awk example)

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Version History Performance and usability improvements. 16 09/05/2025 Performance improvements. Updated content. 14 02/09/2021 Updated interface, new transitions, Quiz mode has been enhanced. 13 01/02/2021 New Quiz mode! 12 10/04/2020 Updated content, full support of iOS Light and Dark modes. 11 09/13/2020 Full support for iOS Dark Mode! 10 12/29/2019 Updated for iOS12! 9 11/13/2018 Revised interface and content.
Updated for iOS11. 8.0 11/14/2017 You can now print any chapter (AirPrinter compatible printer). 7.0 04/17/2017 Updated content.
Optimized for iOS9! 6.0 10/30/2015 Updated interface.
Hi-Res iPads support.
Performance improvements. 5 09/11/2013 Updated interface.
iOS5 navigation fixes. 4.0 12/19/2011 Completely reworked Navigation.
Completely reworked page layout.
Updated content. 2011.1.1 12/19/2010 New by Chapter Navigation
Automatic Bookmarks 2010.5.1 05/17/2010 2010.4.1 04/14/2010