1.: Yes (Slugs differ then, but no need for you to re-categorize each post)
2.: As you wrote: “Information Technology”. As a rule of thumb, Category Names should be between 2 and 26 characters, the actual length depends on your site and your needs as there is no hard nor soft limit to category length and there is no “ideal” or “perfect” category length. This needs to be decided individual based on preference and site content, context and the the current time. See as well your previous question.