I'd like to introduce myself

My name is Denise and I am fairly new to stamp collecting.
My grandmother had actually started a collection for me when I was born, which she left to me when she passed away, making me promise to her that I would continue the collection. I think I was lucky because since she worked in the post office The collection includes posters, change of address cards from the 70s and '80s, short postage cards and receipts for the purchase of the stamps and coins along with other things. She'd even collected the coins that went with the stamps.
I have purchased more stamps since then but I'm really not sure exactly what it is I'm buying, what I'm looking for or if I'm getting ripped off. Basically at this time I'm looking for stamps to complete collections for certain years as well as older stamps, nothing to special or extravagant at the moment. I absolutely love the older stamps, actually any kind of antique captivates me because I love history.
At present time I'm not worried about what a stamp is worth, but I am proud of the collection I have so far. That being said I do need the help and advice from people within the hobby that are more informed regarding the stamps and what I should be looking for. I have a few, that to me, look like they're off print's, but they very well could be normal for that type of stamp.
I also don't understand the abbreviations in the stamp lingo. Some of it I kind of figured out on my own. Some of it I got from the old Scott book that my grandmother had, but it doesn't explain all of them just a few. Mind you it was an old book so that could be a reason as to why not all abbreviations are in it.
I'm hoping that I'm able to learn a lot more within the community from experienced collectors such as yourselfs