I started my programming career with BASIC. It was my 9th grade. I learnt a bit of BASIC by writing simple programs to add, subtract and to print. Then after some years I went to the university and took Computer Information and Systems Engineering. In the first year I was thought C language. I have a good command over C language. Next I learnt C++ in the second year. It just thought me some knowledge of OOP. Now I am currently doing PHP(along with html). I have not mastered C++, BASIC or PHP. I am now planning to move to mobile development. But I feel that I am have not covered everything in the languages I learnt. Does it really matter?