Indeed. There are many ways of generating any frequency. However 50kHz could be real easy for you, depending on what you're using it for. Mains is 50kHz, albeit, a little noisey!
But you could use, a 555 timer, a crystal oscilator, an op-amp oscilator. You need to be more specific. What's it's application? Where are you wanting to use it and in what sort of circuit?