After examining the influence of the Bantu migration on African history, what concepts did the Bantu pass on to the rest of Sub-Saharan Africa? My text for this is Traditions & Encounters, by Bentley and Ziegler.
The Bantu people were originally from West Africa. Over the years, they became the strongest people in Sub-Saharan Africa and spread out to dominate that region. Your text (at the beginning of the chapter) tells us that Bantu people had spread out as far as they were going to by 1000 C.E. It says that they brought two main concepts with them as they spread. These were the concepts of farming and of iron metallurgy.
The Bantu were lucky enough to arise in an area of West Africa that had access to many kinds of crops that could be domesticated. They were also lucky in that most of the other peoples of Sub-Saharan Africa did not have access to such crops. People who farm tend to be stronger (economically and militarily) than those who are hunter gatherers. They tend to have larger populations with more technology. This was true of the Bantu relative to the hunter gatherers they encountered in their movements. This allowed them to spread.
As they spread, they brought with them their crops and their agricultural technologies. Other groups became aware of this way of life through the Bantu. As they spread, they eventually picked up the technique of working iron from peoples in the Rift Valley of East Africa. This gave them even more technology and allowed them to spread further. These were the concepts that they spread as they came to dominate southern Africa.