Can I use elk for free?

I'm curious about the topic of using elk in the context of cryptocurrency or finance. I've come across the question 'Can I use elk for free?' and I'm wondering if you could clarify what elk might be referring to in this scenario. Is elk a platform, a tool, or something else entirely? And if it's possible to use it without any cost, what are the potential limitations or restrictions I should be aware of? Additionally, are there any alternative options available that might be more suitable for my needs?