www18. wolframalpha. com
Description is there in home page. 
Examples:
Go there and enter
integrate (x^2+x^3)dx (click the “show steps” to get a step by step solve)
or graph like
plot sin(x)+tan(x)
So if you want to finish your math assignments quickly to catch IPL matches this is a nice handy thing 🙂
The best thing is that all steps are shown as step by step solve.
Since steps are so beautifully shown they can be directly copy-pasted in any assignment 
No problem like “step jumping”.
Everything does not have definite or finite results.
So their answers are symbolic, in higher mathematics most are symbolic so those calculators cannot give results.
This is actually based on mathematica which (along with maple or matlab ) are used by students in US and europe in mathmatics.
Their life is easier now you may also make you life easier ..
This was posted by my friend cpukid in OUG