Manipulating BGP attributes for route selection

Weight	Affect local router (O/G traffic)	Encourages local traffic to use a specific AS exit point to reach a remote subnet or AS. Ex: For a router to prefer a neighbour over another (IBGP or EBGP) for specific o/g traffic.
Local Preference	Affects local AS IBGP peers (O/G traffic)	Encourages local traffic to use a specific AS exit point to reach a remote subnet or AS. Ex:  For the AS to use one ISP link as main and one to a different ISP as backup.
AS_PATH	Affects remote AS and other upstream ASes (I/C traffic)	Discourages remote traffic from using a specific AS entry point to reach a local subnet. Ex:  For the AS to prefer Web server traffic to enter through a specific link.
MED	Affects directly remote AS only (When there are two links)(I/C traffic)	Discourages remote traffic from using a specific AS entry point to reach a local subnet. Ex:  For the neighbour AS to use one link as main and another as Backup.
Community	Affects remote AS and other upstream ASes	Mark traffic with a community so that neighbor can perform a specific action on it. Ex:  For the BGP peer to apply a specific policy on the traffic.