diff --git a/README.md b/README.md
index 9ac3b60..7486712 100644
--- a/README.md
+++ b/README.md
@@ -57,6 +57,8 @@ Notes:
 
 - Be familiar with Bash job management: `&`, **ctrl-z**, **ctrl-c**, `jobs`, `fg`, `bg`, `kill`, etc.
 
+- Know flow control management xon/xoff : ctrl-s, ctrl-q and shift-PageUp, shift-PageDown to navigate the console screen.
+
 - Know `ssh`, and the basics of passwordless authentication, via `ssh-agent`, `ssh-add`, etc.
 
 - Basic file management: `ls` and `ls -l` (in particular, learn what every column in `ls -l` means), `less`, `head`, `tail` and `tail -f` (or even better, `less +F`), `ln` and `ln -s` (learn the differences and advantages of hard versus soft links), `chown`, `chmod`, `du` (for a quick summary of disk usage: `du -hs *`). For filesystem management, `df`, `mount`, `fdisk`, `mkfs`, `lsblk`.
@@ -126,7 +128,7 @@ Notes:
 
 - Use `man ascii` for a good ASCII table, with hex and decimal values. For general encoding info, `man unicode`, `man utf-8`, and `man latin1` are helpful.
 
-- Use `screen` or [`tmux`](https://tmux.github.io/) to multiplex the screen, especially useful on remote ssh sessions and to detach and re-attach to a session. A more minimal alternative for session persistence only is `dtach`.
+- Use `screen` or [`tmux`](https://tmux.github.io/) to multiplex the screen, especially useful on remote ssh sessions and to detach and re-attach to a session. A more minimal alternative for session persistence only is `dtach`. `byobu` can enhance screen or tmux providing more information and easier management.
 
 - In ssh, knowing how to port tunnel with `-L` or `-D` (and occasionally `-R`) is useful, e.g. to access web sites from a remote server.
 
@@ -168,7 +170,9 @@ Notes:
 
 - For Markdown, HTML, and all kinds of document conversion, try [`pandoc`](http://pandoc.org/).
 
-- If you must handle XML, `xmlstarlet` is old but good.
+- If you must handle XML, `xmlstarlet` is old but good. `Xpath` can be used to query xml files.
+
+- Handling, parsing sgml, html, `onsgmls` can be used.
 
 - For JSON, use [`jq`](http://stedolan.github.io/jq/).