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1. 0:00Programming languages define the rules by which source code can be written.
2. 0:04Over time,
3. 0:05many ways of categorizing programming languages have been developed.
4. 0:09And these categories help organizations decide
5. 0:12which language best fits their systems.
6. 0:14One important factor is the level of abstraction.
7. 0:17This refers to how close the language is to the CPU's binary
8. 0:21environment and how much control it gives the programmer over the system.
9. 0:25Lower order languages such as Assembly
10. 0:27provide direct hardware level interaction.
11. 0:30These require the programmer to understand details
12. 0:33like binary data flows and timing.
13. 0:35High.
14. 0:35Order languages let programmers think more about
15. 0:38solving problems than about machine details.
16. 0:41For example,
17. 0:42in a high order language,
18. 0:43a statement such as Or total equals running total
19. 0:47retail price multiplied by the sum of 1.0 plus
20. 0:51sales tax rate lets the programmer focus on the
21. 0:54math needed for a point of sale application.
22. 0:57In assembly,
23. 0:58this same operation would require a long sequence of instructions like move.
24. 1:02Load,
25. 1:03add and multiply.
26. 1:04This shifts attention away from solving the
27. 1:07business problem and into hardware mechanics.
28. 1:09The compiler translates the high level statement into machine instructions.
29. 1:14Another factor is data type enforcement,
30. 1:17which describes how well a language prevents errors
31. 1:19when working with different types of data.
32. 1:21For example,
33. 1:22you cannot logically add the number 3 to a person's name.
34. 1:26Without enforcement,
35. 1:27these ambiguities can cause.
36. 1:30Data protection or data hiding prevents one software unit
37. 1:33from reading or altering the private data of another.
38. 1:36Code protection or logic hiding prevents one software unit
39. 1:40from altering the source or executable code of another.
40. 1:43These protections help maintain software security and integrity.
41. 1:47Together abstraction,
42. 1:49data type enforcement,
43. 1:51and protections around data and code form