The YouTube video “Apache Iceberg: What It Is and Why Everyone’s Talking About It” by Tim Berglund explains data lakes really well in the opening minutes: https://www.youtube.com/watch?v=TsmhRZElPvM
Thanks but I don’t have the time to watch YouTube.
he explains
~40y ago invented data warehouse, where an ETL process overnight would collect data from smaller dbs into a central db (the data warehouse)
~15y ago, data lake (i.e. hadoop) emerged to address scaling and other things. Same idea but ELT instead of ETL: less focus on schema, collect the data into S3 and transform it later