When you join this site you create an Account - essentially nothing more than your username, an email address and a password. Your Account:
allows you to subscribe to the newsletter;
makes it easier to comment on articles than if you comment anonymously;
allows you to create a Public Profile (next), which in turn allows you to submit content to the site, like News articles, Partner Search profiles, etc.
You apply for an account by filling in the 'Join' form. Your Account is then approved by the ACP S&T Programme Management Unit (PMU).
Your Public Profile is your page on this site - you can tell the community about yourself and where you work, provide a photograph, etc.
Moreover, once you have a Public Profile it will link to everything you contribute to the site: news articles, Partner Search profiles, comments, etc. These links are two-way: your contributions also link back to your Profile, so other visitors can follow your conversations across the site easily.
You can provide most of this information when you initially fill out the 'Join' form if you wish, but it will not go Public at that point, as your Account need to be approved first.
Once it is approved, you can edit your Profile simply by logging in.
More details: see FAQ: How do I register, create and edit my Profile?