The number of shares traded in any purchase usually a minimum of 100. More important is the number traded in a day and the consistency of the volume over the preceding weeks. There is nothing like Volume to attract buyers or attention to a stock. Bigger volume says there is something about the stock investors like and are willing to pay for in order to own a piece of the company. However be carefull when volume skyrockets just before a quarterly or anual report and be ready to sell on the realease of such.
Hence the slogan Buy on Volume __ Sell on news
Personally I like stocks that trade a minimum of 50,000+ shares a day as they offer liquidity when you want to sell.
If you are new to trading I would suggest a couple of things
Before you put a bunch of money in the market, set up a simulator trading acct at such sites as "How the Market Works' and practise trade that will cost you nothing and see how you do. Secondly learn everything you can about Candlstick Charting -- The Buy and sell signals and the trend reversal signals. Also learn about support & resistance and how to use at least 5 supporting indicators. Moving averages, MACD. Stockastics, OBV, Wilders RSI, and money flow. Investorpedia.com has lots of info on trading including some on fundamentals Big Charts .com Never stop trying to learn or reading educational material about the market.
Hope this may be of some Value Lou