What magnification to get?
Binoculars are described with two numbers; e.g., 8 x20, 8 x 42, or 10 x 50 . The first number tells the magnification of the binoculars. The second number tells the size in millimeters of the largest lens, called the objective, where light enters the binoculars.
For your first pair of bird-watching binoculars, start with ones that have either 8x or 10x magnification. Typically, 8x magnification has certain advantages over 10x magnification, those being (a) closer focus, (b) easier to hold steady, (c) wider field of view, and (d) collects more light.
In contrast, 10x magnification binoculars makes the birds look closer than 8x magnification binoculars. This is especially useful if you’re looking at birds at a distance, such as at the beach, at a lake or in a large field.
Before you buy a pair of 10x binoculars, try them out and make sure you can hold them steady since they typically are heavier and any tremor you have will also be magnified more. Also, get a pair that has a larger objective (see #2).