Goldman Sachs Areas/Divisions Clarification Question

Hello! I am a bit confused about this and wanted to seek clarification. 

GS's IBD is said to have 2 focal areas: IBD classic & financing group, with the first encompassing M&As, as noted here (not an exhaustive list of evidence):

• https://www.goldmansachs.com/what-we-do/investmen…
• https://www.linkedin.com/posts/anthonycheung10_go…

However, their IB division is said to be broken up into 6 units with classic, M&A, and financing each being a distinct unit of these 6. 

• https://www.careerprinciples.com/resources/goldma…
• https://www.goldmansachs.com/careers/our-firm/inv…

This isn't very clear for me to understand. Was classic and M&A recently separated with classic being more transactional advice and M&A being advisory for M&A only?

1. I would greatly appreciate clarification as to whether there exists a distinction in units between classic and M&A, and if there is, what this distinction exactly is (given they note that M&A was included within classic). 
2. Or, what exactly entails classic IB at GS?

Thank you very much!