Great article I just read on Medium: 
https://medium.freecodecamp.org/future-of-bitcoin-cc6936ba0b99

He explains in an easy to understand way the issues coming up with the future of Bitcoin: 
- Why transactions are getting slower and fees getting higher.
- What it means to increase the block size from 1MB. 
- What Segwit (segregated witness) is.
- And more. 

Just thought I share it here.