The introductory page contains a large QR code (which is obvious by the alignment boxes around the image, and the black and white patterning) and a progress bar.
If you take the URL of the QR code image, http://ctf.infosecinstitute.com/img/qrcode.png, and paste it into a QR code decoder, you get the following blob back:
.. -. ..-. --- ... . -.-. ..-. .-.. .- --. .. ... -- --- .-. ... .. -. --.
This is morse code - an encoding algorithm that represents the alphabet as a series of short and long pulses (dots and dashes) used before we could send complex data over the Internet (think telegraphs).
Putting this text into a morse code decoder you get the text:
INFOSECFLAGISMORSING
INFOSECFLAGISMORSING