Convert images to a PDF file:
sudo apt install img2pdf # If not installed already img2pdf im1.png im2.jpg -o out.pdf
Source: https://stackoverflow.com/a/8955457/526189
Convert images
sudo apt-get install imagemagick convert source.png dest.jpg
Source: https://askubuntu.com/a/13825/118883
Copy ISO image to USB drive
dd if=/path/to/your/isofile of=/your/usb/disk bs=8M status=progress
Source: https://superuser.com/a/351815/101527
Convert PDF files to text files
sudo apt install poppler-utils pdftotext input.pdf output.txt
Sources: cyberciti, linuxuprising
Colored cat
alias ccat='highlight -O ansi --force' ccat file
Source: https://stackoverflow.com/a/27501509/526189
Bash – get file name and extension
filename=$(basename -- "$fullfile")
extension="${filename##*.}"
filename="${filename%.*}"