Let´s see how it works.
This is an interactive chart showing the progress of Segwit
It seems this week most people are starting using the Segwit address (like mine they start with a number three: 38weBCNrodHtUc8WihrLXxHY4tR8Ee33eb )
Most people with old addresses are changing from one old to the one new, thanks to the low fees implemented these several weeks
According to wikipedia:
It does this by splitting the transaction into two segments, removing the unlocking signature (“witness” data) from the original portion and appending it as a separate structure at the end. The original section would continue to hold the sender and receiver data, and the new “witness” structure would contain scripts and signatures. The original data segment would be counted normally, but the “witness” segment would, in effect, be counted as a quarter of its real size.
This is a nice video extremely simple, but it can help to grasp the idea of Segwit:
and after that in case something with more info:
I really like the second one.
Take a look a both videos and let me know what you think.