This book is a collection of notes and sample codes written by the author while he was learning email systems. Topics include email message transmission protocols: SMTP, IMAP, POP3; secure connections with SSL/TLS protocols; managing Postfix server as MSA, MTA and MDA agents; managing Dovecot server for email retrieval with IMAP and POP3 protocols; Thunderbird and other email client tools. Updated in 2024 (Version v1.03) with minor updates. For latest updates and free sample chapters, visit https://www.herongyang.com/Email.

This book is a collection of notes and sample codes written by the author while he was learning Linux systems. Topics include using Cockpit Web portal for admin tasks; managing users and groups; managing files and directories; managing NTFS, CIFS, EXT4, LBA, LVM file systems; using network tools and security firewall; installing CentOS systems; using SELinux (Security-Enhanced Linux) system; DNF/YUM software package manager; SSH Server configuration and client tools; managing vsftpd - Very Secure FTP daemon; managing directory service with OpenLDAP; Updated in 2024 (Version v5.44) with email topics moved to 'Email Tutorials' book. For latest updates and free sample chapters, visit https://www.herongyang.com/Linux.

This tutorial book is a collection of notes and sample codes written by the author while he was learning PKI (Public Key Infrastructure) technologies himself. Topics include Root CA (Certificate Authorities); SSL, TLS, and HTTPS; Server and client authentication processes; Communication data encryption; Using HTTPS with Chrome, Firefox, Edge, Safari and Internet Explorer; Managing certificates on Windows, macOS, iOS and Android systems; X.509 certificate format; Certificate store and management tools; Certificate validation chain; Self-signed certificate and CSR; Digital signature on MS Word and OpenOffice documents; Get free personal certificate from Comodo. Updated in 2022 (Version v2.31) with macOS and Safari tutorials. For latest updates and free sample chapters, visit https://www.herongyang.com/PKI.

This PHP tutorial book is a collection of notes and sample codes written by the author while he was learning PHP himself. Topics include PHP script syntax; data types, variables, array, expressions, statements and functions; Web server integration; HTTP requests and controlling HTTP responses; sessions, cookies, and file uploads/downloads; MySQL database server access; files, directories, and ZIP archives; parsing HTML Documents; processing image files; SOAP extension; managing non-ASCII characters; classes and objects; using PHP on Windows, macOS and Linux; executing external programs on operating system. Updated in 2022 (Version v5.16) with minor changes. For latest updates and free sample chapters, visit https://www.herongyang.com/PHP.

This book is a collection of notes and sample codes written by the author while he was learning Linux applications. Topics include using managing users and groups; managing files and directories; managing Apache Web server and SquirrelMail; managing MySQL server; developing Python and PHP scripts; using GCC C/C++ compilers; running graphical applications on GNOME desktop and X11 servers; running Conda - Environment and Package Manager. Updated in 2023 (Version v1.02) with minor updates. For latest updates and free sample chapters, visit https://www.herongyang.com/Linux-Apps.

This book is a collection of tutorial notes and example codes written by the author while he was learning different data encoding algorithms. Topics include introduction of data encoding algorithms: Base32, Base64, UUEncode; Base64 Encoding Algorithm with W3C Implementation; Base64 Encoding tools and API in Java, Python, PHP and Perl; Base67URL Encoding to be URL and Filename safe; Base32 Encoding Algorithm with Java, PHP and C++ Implementations; URI/URL encoding with Java and PHP example programs; application/x-www-form-urlencoded encoding with Java and PHP example programs; UUEncode Encoding Algorithm with Sun Implementation. Updated in 2023 (Version v5.23) with minor changes. For latest updates and free sample chapters, visit https://www.herongyang.com/Encoding.

This VBScript tutorial book is a collection of notes and code samples written by the author while he was learning VBScript (Visual Basic Scripting Edition) himself. Topics include: The Variant Data Type with Subtypes; Fixed-Size and Dynamic-Size Arrays; Function Arguments Passed by References and by Values; Raising and Catching Runtime Errors; Regular Expression and Pattern Match; Runtime DLL Library: Dictionary, File System, and File I/O; Defining Classes with Properties and Default Method; Object Initializing and Terminating Processes; Client-Side Scripting: VBScript Code for IE Browser; Server-Side Scripting: VBScript code for IIS Server; System Admin Scripting: Windows Script Host (WSH). Updated in 2024 (Version v6.03) with minor changes. For latest updates and free sample chapters, visit https://www.herongyang.com/VBScript.