It's a common question - "What do you actually do?" Fair question to ask. OK, here's what's involved in creating a professional web site.
This involves determining the best structure for the site - pages, sub-pages, navigation, header, footer, sidebar(s), layout, formatting of quotes, images, designing in the integration with social media, thinking about usability, accessibility, typefaces, type sizes, colours, logo and branding. Much of this has to be considered for different screen widths to ensure it all looks good and operates properly on mobiles, tablets and desktops.
If we produce the content then it has to be researched, written, keyword optimised, checked and proofread. We may also source photos and graphics.
We have to take decisions on what happens next, e.g. what happens when I click this button? This is usually more of an issue for online shops than other types of web site.
This entails compressing photos to the minimum number of bytes without visible loss of quality. We would also compress code as well so that your web pages load as quickly as possible which is especially important on mobile devices where the mobile network runs more slowly than broadband. It's also a factor that Google uses in determining the position your site will appear in the search results.
We test to ensure your site looks and works as expected on many desktop browsers (Chrome, Firefox, Internet Explorer, Safari, Opera) and desktop operating systems (PC and Mac) as well as on tablets (iPad and Android) and a variety of smartphones (iPhone and Android). This phase tends to take longer for online shops as there is more to test.
Promotion of the code, photos, graphics, videos, database etc. to the live server, set up site maps, statistics collection and check that all is working as expected.
That's a quick, high level run through of what is needed but please do ask in the comments below if there is anything not mentioned that you thinks should be here.