Please find links to my articles on SAP ABAP in an organized way. ABAP is the programming language of SAP and is a language of long-standing tradition. It has history of around 35 years of evolution. I have included resources helpful in learning the language.
Even if your interests lie somewhere else in the area of SAP, it's a good idea to get some basic understanding of this area. Knowledge of ABAP basics can give you an edge in other SAP areas. Though a minimum amount of ABAP knowledge is becoming a trend in the industry, but if you are a business process expert / functional consultant with fairly good SAP ABAP knowledge, you are distinguished as techno-functional consultant.