Microsoft Office is one of the most common applications used in the world today. Having extended knowledge on use and support is a must have skillset.
Listed in this linked website is a pile of acronyms that I find most common in server management and other aspects of my job. Have a look and feel free to search and learn what these items are.
One of the main issues I have all the time is a user that only knows how to do their job and nothing more. Get curious and investigate how to mange your computer and where items and settings are located.
Knowing how to manage a web browser and help staff set them up and operate them is a key function of providing good support for your users.
This has some basics on client server design and how most Windows computer systems work today. There are other definitions worth reading on as well.
When using a computer as a user and later as a system admin you need to know about the options and importance of the following items on this site.
There is always a need to know how things work in relation to how items are connected together. Don't have to know every detail but should become familiar with items and terminology.
I have learned most of my skills from the Internet over the years. A majority of solutions for issues are also found on the Internet. Having good search habits help you find the solution to your issues faster. Review the Common search techniques like Search for an exact match.
I cannot stress enough that you need to sound like you know what you are talking about. Also don't be afraid to ask questions, they want you to learn. Every time I start a new job there is always lingo used at the office I have to learn about their infrastructure because everyone's is a bit different.