Investment involves sacrificing current consumption for future benefits through purchasing assets that are not necessarily marketable in the short term. It is a well-thought process that considers risk and expected return. Speculation, on the other hand, does not guarantee return of principal and involves purchasing assets with the goal of profiting from short-term price changes rather than long-term growth. Speculators are more focused on insider information and market trends over stable income generation. Overall, investment is a longer-term commitment while speculation aims to profit from price volatility in a short time period.