SED (Unix stream editor) is a very powerful shell scripting tool, particularly useful for file manipulation, in data cleansing exercises etc. 

Like awk (and nawk) we have used sed extensively in many of the data cleansing exercises we've been involved in..

Convert TAB file to CSV

The following sed code snippet is a simple way to convert a tab delimited file to a CSV style file 

sed -e 's/"/\\"/g; s/^/"/; s/$/"/; s/\t/","/g' myfile > newfile.csv

Training Notes

As well as writing awk, sed and other shell scripts, we also deliver training courses.

Attached is a training document that we prepared (quite a long time ago) for a sed training session, please use it.

AWK Training Notes