[R] Table Help

[McMurtry, Benjamin G.]

I have a very large table that I want to add some of the certain rows.

The table is as follows:

Username1 2
Username1 4
Username2 6
Username2 10
Username3 12
Username3 10
Username3 16

Etc ....

The data is sorted by Column 1 (Ie the username) then by columm 2 (The
numbers).  I do not know how many of each username I will have.

I want to combine the rows so it would be as follows:

Username1 6
Username2 16
Username3 38 

Is there  easy way using a feature like bind to sum all of collumn two where
column 1 is the same?

Thanks!
Ben