What is wrong with our computer???

For about a month now our computer has been acting really strange. Sometimes it works and sometimes it doesn't......and sometimes it runs really really slow. That's the worst....when it runs really really slow. I just get so frustrated that I end up turning it off and then coming back to it later. When the internet is working I try and get the most important stuff done......mainly bills, and keep putting off blogging. Well, here I am.....I'm not putting it off any longer. Besides I have to blog about our holidays and the places we have been.