Thanks in advance for you help.
There are many ways to load data into HDFS and many ways to run applications in HDFS. The broad diversity of tools and variety of apps and solutions gives Hadoop great power and flexibility to store, process and analyze:
all in one centralized data store (HDFS). Doing so allows the business to better execute what they are already doing (e.g. lower cost data warehousing) and to implement new capabilities that were not before possible (e.g. applications based on predictive analytics or a 360 degree view of the customer).
As a high level answer to your question. You can load and run programs in HDFS from:
The best way to start understanding the components and capabilities of hadoop is http://hortonworks.com/apache/
The best way to get started in becoming a Big Data expert is https://hortonworks.com/developers/