Newer investors should pay attention to a number of factors before putting their money to work. One of those factors are the stock investments by industry that they make. Should they load up on stocks from the technology sector because they hear the names of those companies batted around in the news? Does it make more sense to buy some consumer staples because they are more likely to interact with these brands on a regular basis? These are the questions to think about before making stock investments by industry.  
The industry of the stock is simply the type of business that the company is involved in. It can range from health care to manufacturing, from retail to semiconductors. There are a lot of industries that companies get categorized into, and it is vital to familiarize oneself with those industries so as to better understand which industries make the most sense for your portfolio.  
The most sensible piece of advice is to only invest in industries that you reasonably understand. In other words, don’t put your money to work in something that you cannot explain to a relative in just a few sentences. You are probably stepping beyond your bounds if you lay down money in something overly complicated.  
The particular industry that you put your investments in may be balanced based on the relative performance of that industry versus the others (i.e. buying industries that are selling cheaply at the moment), or it may be related to which industries you have the most personal knowledge of. Finally, some people decide to buy into industries based on their risk tolerance. For example, technology can be seen as a high-risk, high-reward kind of investment, but on the other end of the spectrum you have utilities which are considered very stable and reliable. Sometimes it is just about setting risk tolerance parameters and running with that.