You will find dal being cooked practically in every Indian home. It forms an integral part of Indian meal and everyone from young to old, rich to poor enjoy it. Dal or lentils is the staple food in every Indian home, both the rich and the common person who lives on the street –

Dal preparations can be eaten with rice, as well as Indian breads in North India. In India, it is eaten with rice and with a wheat flatbread called roti. The manner in which it is cooked and presented varies by region.

Dal has an exceptional nutritional profile. It provides an excellent source of protein, particularly for those adopting vegetarian diets or diets which do not contain much meat. It is typically around 25% protein by weight, giving it a comparable protein content to meats. It is also high in carbohydrates whilst being virtually fat-free. It is also rich in the B vitamins thiamine and folic acid, as well as several minerals, notably iron and zinc.
Here are some guidelines on how to cook Lentils/dal/dhal/grams/peas:

Dal or lentils is the staple food in every Indian home. Both the rich and the common person who lives on the street enjoy it. It is what chicken is to the west – it is India’s comfort food and also It’s usually the starter of every meal eaten with hot steaming rice or with freshly made chapati (leavened bread) straight off the girdle. Dal is everyman’s meal and one of the healthy dishes in an otherwise red hot-chilly pepper Indian diet. The desert cuisines of Indians use an immense variety of pulses and preserves to substitute for the relative lack of fresh vegetables.  It is also dried with spices to produce spice capsules to add to foods. The world of dal in India is truly one of India's culinary gem. 
Most dals do not need soaking.  They may be boiled with turmeric and ginger and then seasoned with sautéed onion and tomatoes.  Roasted or oil sizzled cumin seeds adds an extra dimension to dals and aids in digestion of dals.
Tempering Dal
The tempering, or seasoning, is what makes the dal come alive.  Turmeric gives dal the lovely golden hue. Dal is fat free and nature has designed it to absorb various combinations of seasonings and spices.  There are innumerable variations of the simple seasoning and one can create their own individual taste. The standard ingredients include mustard seeds, jeers, red chilies or chili powder, hing/asafetida, onions, green chilies, ginger, garlic, tomatoes, garam masala, curry leaves. The fat of choice is ghee in the dal.  Oil brings in a acidic after taste but if one is a vegan we suggest sunflower oil.  seasonings are enhances in the ghee medium pushing their curative properties higher.  Dals are commonly garnished with fresh chopped coriander and served hot.

VARIETIES OF DALS
Toor dal, i.e. yellow pigeon peas, is available either plain or oily.
Chana dal is produced by removing the outer layer of kala chana (black chickpeas) and then splitting the kernel.
Yellow split peas
Kabuli dal, known for its black coat, is an average-sized chickpea. It grows naturally with the black coat, and it is said to be nuttier in flavor
Mung dal is also known as mung bean.
Lobiya dal – black-eyed bean
Urad dal, sometimes referred to as "black gram"
Masoor dal is red lentils
Rajma dal – kidney beans

For Pressure Cooking there is no need of soaking the lentils.  If you are going to cook lentils often it would be a good idea to invest in a pressure cooker

Cooking in a pot with a cover – Once the dal comes to a boil, remember to cover it and set on a low flame. While cooking on the stove allows you to constantly check the dal's water level, it takes a lot more time.