The 071 is a called Bi-FET design. The input part of the amplifier uses Field Effect Transistors and the output part uses Bipolar Transistors. This means the op-amp can have all the benefits of each sort of transistor. The pinout (what pins on the package are connected to what) of the 071 is the same as the 741, making it a drop-in replacement.
The FET input means that the op-amp has a very high input resistance and only needs a tiny input current to work. This means it is easy to ‘drive’ - i.e. the signal source doesn't have to supply much current. The Bipolar output means that the op-amp can provide just as much output current as an all-bipolar design could.
The TL072 is a ‘dual’ version of the 071, allowing you to get more op-amps onto a circuit-board. If you need even more, there is also the TL074 which is a ‘quad’ and fits four op-amps onto a 14 pin DIL pack. The 072 has the same performance as the 071, but the performance of the 074 is slightly poorer as a sacrifice for fitting so much into one pack.

The TL071/2/4 family was originally produced by Texas Instruments. These days there are lots of near equivalents which mix FETs and Bipolars to get the same advantages. For general purpose signal amplification, filtering, etc, etc, they are often the best choice as they make circuit design simple and the circuits tend to work without any serious practical limits.

There are also an 061/2/4 family and an 081/2/4 family. They have the same pinouts and are quite similar, but have a higher noise level in exchange for higher speed or lower bias current. When in doubt, choose the 071 family unless it doesn't meet one of your needs.

 Typical values of Basic Parameters:

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