There are two types of lag:
Graphical Lag: A low frame-per-second rate, which will make everything look jerky. Turning down graphics settings and resolution improves this.
Connection Lag: Whenever it says "there is a problem with your connection". Also includes when players are move jerkily. This is caused by: the server, your connection speed, how close the server is to you, whether you have wireless, or a combination of the above.
So don't try and solve conenction problems by turning down graphics.
Graphical Lag: A low frame-per-second rate, which will make everything look jerky. Turning down graphics settings and resolution improves this.
Connection Lag: Whenever it says "there is a problem with your connection". Also includes when players are move jerkily. This is caused by: the server, your connection speed, how close the server is to you, whether you have wireless, or a combination of the above.
So don't try and solve conenction problems by turning down graphics.