I have a huge problem while reading computer books. Every couple pages I'll end up googling something I want to learn more about, but then I'll find something on that page that I'll want to learn more about and google that (sometimes programming related, sometime hardware related).

Normally after wasting around 3 hours going into different subjects I'll return to the original text only to repeat the process a few pages later. Any advice for sticking to one subject and learning that in-depth?

I have tons of programming books I've read half-way through since I'll become interested in other languages/topics (not that I'm not interested in the books I've started).

Also, what would be worth focusing on in depth? I've gone into Python in the most depth but for classes I'm learning Java and assembly (ARM and Motorola 68000). Also, I've taken a class on C++. Lately I've been spending most of my time learning about Linux instead of programming though. I'm not sure what would be worth focusing on the most to get a job.

In other words, how can you focus on one topic and not let curiosity about everything else get in the way?

Thanks in advance, Brian