Why aren't my new files appearing in my GitHub repository?

I have created a repository, now I have worked on about 5 source files but they dont appear online. How do I upload them/make them show online.

Secondly, how do I allow other people to use the repository? What I mean is, the project is a four-per开发者_开发百科son thing so how do the others join and how do I control uploaded files?

First you need to commit your changes locally before you end off with push to sync your repository with the one on github, e.g.

git add .
git commit -m "Some changes"
git push origin master

You need to commit and push your changes for them to show up online. Assuming you have already followed the steps GitHub gives you to link your local repository to the remote master, this is accomplished with a simple

git add .
git commit
git push

And adding additional contributors isn't too tricky, just go to the project, click the Admin button in the upper right corner, click the Collaborators tab, and add their github accounts.

This is really a question that is easily answered by the wonderful git and github documentation. Check out http://help.github.com/ for all of this and more. StackOverflow is for questions about programming, not about how to set up repositories (and it also shouldn't be used for questions that can be easily answered by existing documentation).