If your field requires you to use equations regularly, and especially if you plan to write a paper or publish an article or book that includes multiple and complex equations, the computer language that you are likely to have to use is called LaTeX. LaTeX, originally developed in the 1980s by Leslie Lamport, allows you to generate camera-ready format and equations using predefined macros rather than all manual text. If you need to publish your material on the web, LaTeX is especially valuable, since you can easily convert an equation to a pdf and post it on the web in a format that will be readable no matter what browser your reader is using.
Writers unfamiliar with using LaTeX tend to start with a tutorial, such as this basic "quick and dirty" LaTeX tutorial, this one from Drexel University, or with Leslie Lamport’s definitive book LaTeX: A Document Preparation System.
Free tips and tricks for using LaTeX abound on the web. Here are two recommended sites: