SIP as Systematic Investment Plan, is a part of Mutual Fund. It's the plan that enables you to invest small fixed amount in regular interval and fund manager will handle your money in different instruments. This is very affordable for low income class, where they can invest minimum Rs. 500 per month in order to create wealth in the long horizon. I hope you understands this basic level.
You can also invest in SIP order to save tax under section 80-C through ELSS fund (which is part of Mutual Fund, especially for Tax-saver). But ELSS has 3 years lock-in period.
The opposite of SIP is Lumpsum in Mutual Fund, which is one time lump payment.
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