Summary:
When you are just starting out playing cricket it is not always easy to decide what you need to buy. If you go into a sports store and ask them what you need, you will end up getting a lot of equipment. So it is best to work out what you need before you go shopping. That way you are more likely to get what you need, rather than what the store owner thinks you need.
Below, is more or less a comprehensive cricket equipment list, you don't need everything on this list, as man...
When you are just starting out playing cricket it is not always easy to decide what you need to buy. If you go into a sports store and ask them what you need, you will end up getting a lot of equipment. So it is best to work out what you need before you go shopping. That way you are more likely to get what you need, rather than what the store owner thinks you need.
Below, is more or less a comprehensive cricket equipment list, you don't need everything on this list, as many clubs will lend you equipment especially at junior level:
Cricket whites, cricket bat, ball, helmet, gloves, batting (wicket keeping) inner gloves, wicket keeping gloves, batting pads, wicket keeping pads, box, chest pad, arm guard, inner thigh pad, cricket boots (bowling boots; batting boots), box (groin guard), stumps and bails.
For most games that you play you will need your own set of whites. Cricket whites consist of white cricket trousers and cricket shirt. Make sure that you get a proper pair of cricket trousers and also a good white cricket shirt and jumper as it can get cold if you are standing out on the field for a long time especially if you are playing in England (the start and end of the season are the coldest).
If you can not borrow equipment from your club the other most important items of equipment are a cricket bat and box. A good cricket bat is essential if you intend to score lots of runs and is a very personal piece of equipment, spend some time choosing your bat, ideally you should go to a shop and pick one up beofre you buy so you know how it feels to play with. (Once you know what you want you can often buy bats online cheaper). You need a good box to protect your groin from the ball, as getting hit 'down below' is extremely painful (I know from experience), so investing in a good box before you start is a must - you can't bat without one.
Cricket batting pads and batting gloves are the next most important thing that you need when you are starting to play (often you should be able to borrow them from your team mates or club if you can't buy them). Cricket pads will protect your legs and if you get a good pair they will make you much more comfortable on the pitch. When you are buying pads, it is also better to go to the store to make sure that you get a pair that fit you and are easy for you to wear and to play in. Even if you see a pair that look good at an online, you would be better to pay a bit more in the store so that you make sure that you get a pair that is right for you. Cricket batting gloves are also important to protect you hands when you are batting, as fingers can be easily broken when hit with a hard cricket ball.
If you are young player it is a good idea to buy a helmet to keep your head safe from any high balls or balls that deflect off your bat towards your face. Regulations now mean that young players under 18 have to wear helmets when batting (or if you're a wicket keeper if you are standing up). You might be able to borrow a helmet from your team mates or club but if you are serious about your cricket it's definitely worth investing in one.
Serious cricketers should also invest in a pair of cricket boots. As it is very important to buy these as your feet can suffer if you do not have the right shoes. Having the cricket ball hit your toes when batting is very painful and good pair of cricket boots will provide more protection than a simple pair of trainers.
You do not need a huge amount of gear to play cricket, as often you can borrow gear from your team mates or club, plus if you invest in high quality cricket equipment then it will last you a very long time as well.