Append Columns From One Table To Another

Perhaps this is a common request : I have 2 tables:

Table A
-------
ID Value
1 a
2 b
3 c

Table B
-------
ID AnotherValue
1 x
2 y

I am hoping to append a column from Table B to Table A based on a simple sql join (e.g:

Table A

ID Value AnotherValue
1 a x
2 b y
3 c (null)

)

I would rather stay away from the standard update statement since it takes far to long and I'd prefer not to use create table as I don't want to duplicate any data...is this possible to do ? (e.g: just insert the columns into this table ?) - or if it's possible the performance overhead just wouldn't make it worth it ?