Are you making a web site?
You will need to know:
Responsive design, HTML5, CSS, JavaScript, PHP, MySQL, FreeBSD, Apache, Postfix, Dirvish, rsync, SSH, FTP, Perl,
Firefox, Opera, Safari, Chrome, Internet Explorer 6, Internet Explorer 7+8+9+10,
Windows, Unix, Linux, Android, Mac, iPad, iPhone, handheld devices,
domain names, URLs, cookies, meta tags, HTTP,
UTF-8, encoding, SQL injection, spam protection, encryption, database design, systems architecture, server tuning, web hosting,
browser quirks, UX design, usability, user interfaces, Photoshop, web design, web publishing,
integration, documentation, compatibility, validity, accessibility,
search engine optimization (SEO), algorithm optimization,
Geonames, GeoIP, Google Map API, geolocation, Facebook, Twitter,
favicons, Opensearch, web services, SOAP, CAPTCHA, NTP, DNS, SMS, MMS, CMS, RSS, and/or AJAX.
Or you could hire someone who knows.