The Intel have introduced both processors, Pentium and Celeron. The basic difference between Celeron and Pentium is the areas of bus speed and L2 cache features. First time, the Celeron was introduced without any L2 cache at all. This thing degrade the value of Celeron or in other words this deficiency punished Celeron performance as compared to Pentium. Here are some differences and similarities between the Pentium and the Celeron Processors. First difference between the Pentium & Celeron is Cache. A Celeron might have 128 k.b of L2 cache whereas a Pentium 4 can have four times more. Every computer expert knows that the amount of L2 cache memory have a big effect on performance. 2nd thing is Clock speed. Intel Pentium chips have a higher Clock speed than Celeron chips. The clock speed is determining factor in how fast a processor is and usually the higher Pentium 4 processors are 60% faster than the highest Celeron processor. 3rd thing is Buss Speed. The Pentium 4 processor tend to be about 30% faster than Celeron processor.
The smaller L2 cache size and low bus speed beats Celeron processor. If you want to do simple work like composing, use of internet then Celeron is better. There is another advantage of Celeron that you can save a lot of money. But if you want fastest system bus and higher clock speed then Pentium is better. For example if you want to use any heavy software like movie editing software then Pentium is best. Celeron will not give the best performance in that case.