If you are wondering what the two terms signify: the first one is Equity Linked Savings Scheme and the other National Savings Scheme. So, if you are looking to go for some tax savings, then, in my opinion these two schemes are best available in the market (as of now).
The former offers good returns but is market driven with a lock-in period of 3 years, whereas the latter ensures a fixed return but it comes with a longer lock-in period of 6 years. So, for those who are looking for short-term benefits might opt to go for the former and if you are patient enough to wait for a couple of more years then you might chose the latter.
One thing that you should watch out for is what impact the introduction of Direct Tax Code (DTC) will have on these schemes. As far as I know, the introduction of DTC next year will phase out ELSS. So, one should be cautious while investing in the same.
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