The job will REALLY depend on the company and what their product is. However, in theory software testing usually involves the following:
- Comptilbity testing (Will it work on different OSs, languages, service packs, with other packages installed)
- Regression testing (does it work as well as the previous version, did anything break along the way)
- Performance testing (Actual thruput of the software, as well as baseline requirements, memory footprint, etc)
- Stress testing (accelerated real world tests, will it run for a year straight w/out memory leaks etc)
- Usability testing (studying how people interact with the software)
- UI Testing (testing the technicalities of the UI)
- Functionality testing (does it actually do what it's supposed to do)
- Automated testing (testing interfaces or processes to ensure that data that goes in always comes out the same way)
And probably a few other sweeping generalities that I've left off. Depending on who you work for and what your position inside their test structure is, you could be doing any or all of those things, to varying degrees of intensity.
Aha,
your link said much the same thing. Looks like you'd be a QA consultant for hire out to other companies? Read those descriptions, they are reasonable detailed in what services they offer.