Question about COBOL Study Notes

I have recently started learning Cobol. Of course, I need to understand some background and application fields and prospects for learning a language. Let's talk about my questions and understanding.

1. How old is Cobol?
For this question, read a book and check the information. COBOL is the abbreviation of common business oriented language. It is mainly used to solve a large number of data processing problems in business and enterprise management fields, also known as Enterprise Management Language and data processing language. The development of the COBOL language began in the late 1950s S. At that time, computer production had entered the second generation, and the computer application field began to expand from numerical computing to data processing. The amount of data that needs to be processed in business and enterprise transaction management has increased dramatically.ProgramDesign Language to improve the quality and speed of programming. The COBOL language came into being in this context. That is to say, COBOL has been more than half a hundred years old. COBOL was officially released in April 1960, known as Cobol-60. Now the latest version should be Cobol-2002, and it is still being improved, the future of COBOL will support XML and other new web era technology. In other words, COBOL will continue ......

2. Why don't I retire when my COBOL is so old?
As a seniorProgramming Language. COBOL has a large user base andCodeIt is said that programs written in COBOL exceed 100 billion lines (cobol.org ). Another survey found that 70% of the commercial applications currently used in the world are written in COBOL code, and the annual growth rate is about 5 billion lines of code. It seems that history has given the COBOL language a special mission. In addition, as long as the mainframe exists, it also needs to run the COBOL program, and many senior programmers are used to the COBOL. New programmers (such as me) who join the mainframe environment also have to start using the COBOL program. In fact, COBOL also has some advantages, such as its strong control over the data display format. In addition, I think the most important thing is that even for IT companies with considerable experience, re-writing reliable application software is impractical or not feasible from a commercial perspective, it also takes a long time.

3. What are the main application fields of Cobol?
As described above, COBOL is mainly used in commercial data processing. The largest percentage is in the banking, financial, and accounting industries, followed by computer var/retail/Consulting (? , Retail, consulting) industry, this is the United States survey data. The Application of COBOL in China should be similar.

4. On which machines can COBOL run?
COBOL was originally used for host systems, such as IBM mainframe and middleware. With the widespread use of PC, some manufacturers have also released compilers on PC. However, I have been unable to find any PC compiler or editor for a long time ~, I still haven't read a lot of information. I will try again later.

5. Does COBOL Support databases?
This problem is due to the fact that in the COBOL textbook, COBOL is file-oriented and a typical language for data processing by file system. There is no doubt that if COBOL does not support databases, it will be useless in modern commercial applications. Therefore, this question must be certain. As for the specific content, we are learning, I can't say why.

for the time being, I have so many questions and I have learned so much about it.