As an author, it is very important for you to know what rights you have to your own work. These rights determine whether you can include your work in a repository, republish it in a collection, or distribute it to your colleagues.
For the most part, your rights in your work are governed by the contract you sign with your publisher. Thus, it's important to read that contract carefully!
Many publishers offer an option to make the published version of your work publicly available upon publication, for a fee (often quite a large one).
However, in most cases, you can also make your work publicly available without paying. The difference lies in:
Most large academic publishers (such as Wiley, Elsevier, Taylor & Francis, Springer, Routledge, etc) allow authors to make their accepted manuscript available online, after an embargo period. I'll cover both of those concepts below.
Here are some issues to check for in your contract:
Your agreement with the publisher determines the extent to which you are allowed to distribute your own work, so it's important to read it carefully!
Your agreement with the publisher determines what you can do with your work!
Publisher agreements might allow or disallow these uses!
Publisher's policies have grown more complex, since they offer different contracts to authors who have paid fees than to those who haven't; this process has made SHERPARomeo a little bit more difficult to use. If you find the symbols confusing, you can find links at the bottom of the page to the actual policy.
Or, you can ask me! I'm not a lawyer and can't offer legal advice, but I do have some experience reading these policies and am happy to go over them with you.
Otherwise, check your contract! It should spell out what you can do. Pay particular attention to your rights regarding archiving.
Multiple versions of a work are usually involved during the publication process. To simplify, publishers usually refer to three different stages:
Most publishers will allow you to share the Accepted Manuscript, so it's a good idea to save a copy.
Publishers' policies often impose an embargo, or waiting period, between the time of publication and when you can share your accepted manuscript. You can usually find this length of this embargo on the publisher's website or in your contract.
If it seems difficult to remember that you'll be able to share your article many months after publication, note that there are ways to automate this. For instance, if you submit your work to CUNY Academic Works, there is a feature which allows you to input the length of the embargo, with the work becoming automatically available once the embargo expires.
If you are publishing a book, it's less likely that the publisher will have a blanket policy covering all their publications. The contract will govern what you can do with your work. Thus, it's important to understand your contract and, if this is important to you, to negotiate for those rights.
Some good advice in this respect can be found in this guide by the Authors' Alliance: