In pet food, beef can be used as a fresh meat (fresh beef, deboned beef, freshly prepared beef) or as a pre-prepared, dry meat meal (beef meal, dried beef, dehydrated beef). When the ingredient is listed simply as 'beef' it usually refers to the fresh form.
Although the quality of beef used in pet foods can vary, it is generally regarded as a highly digestible, highly palatable meat source for dogs. In the past, some pet food manufacturers had labelled beef as a problematic meat for dogs but solid evidence is hard to come by.
Red meats like beef do, however, contain higher levels of cholesterol which should be kept to a minimum if your dog has a history of health problems. Red meats also contain higher levels of purines and other minerals (especially in the 'meal' form due to the higher bone content) which are best avoided in dogs with urinary conditions.