I've been mixing up masculine and feminine forms--in part, I think, because I learned Spanish before Hindi, and the -a ending in Spanish is feminine. In Hindi, it is masculine. To keep it all straight, these are the general forms (i.e., there are plenty of exceptions) for Hindi words.

कौन who

क्या what

कहाँ where

कब when

क्यों why

कैसा/कैसी/कैसे how, what kind

कितना/कितनी/कितने how much, how many

The seventh and final group of consonants -- श, ष, स, ह -- is the fricative consonants ( Fricative consonants). As an aerospace engineer, fricatives are easy for me to understand. Fricatives are formed by forcing the air from your lungs into a tight channel and causing turbulence in the air flow; it's like placing a model in a wind tunnel.

श
śa, /ɕ,ʃ/

ष
ṣa, /ʂ/

श and ष are essentially two flavors of sh. श (śa) is a palatal consonant, so it should be articulated with the top of the tongue against the palate. ष (ṣa) is a cerebral consonant, so it should be articulated with the tip of the tongue placed against the palate, behind the location where श is articulated. So, for me, an American, it is a matter of getting the tongue placement right.

स
sa, /s/

ह
ha, /h,ɦ/

स and ह are just like their English transliterated counterparts, sa and ha. They are very common letters, as well. The alphabetical order of the first five groups of consonants followed rows in the table below. However, the alphabetical order of the sixth and seventh groups follows the columns. Thus, the alphabetical order is: (labials) प, फ, ब, भ, म; (approximants) य, र, ल, व; (fricatives) श, ष, स, ह.

I am archiving this information about the alphabet on the Hindi page: kirkkittell.com/language/hindi. More information from Wikipedia:

• Approximant consonants
• Sounds represented within /.../, e.g., /k/, are symbols of the International Phonetic Alphabet (IPA), which is extremely useful for me to understand how Hindi sounds.
• Sounds such as ka are transliterations from the International Alphabet of Sanskrit Transliteration (IAST). It's simpler to understand than IPA.

The sixth group of consonants -- य, र, ल, व -- is the approximant consonants ( Approximant consonants). The approximants sound similar to their corresponding English consonants, as shown in the transliterations below. Approximants are special because they resemble vowels -- a sort of middle sound between vowels and consonants.

य
ya, /j/

र
ra, /r/

ब
la, /l/

ल
va, /ʋ/

The alphabetical order of the previous five groups of consonants followed rows in the table below. However, the alphabetical order of the sixth and seventh groups follows the columns. Thus, the alphabetical order is: (labials) प, फ, ब, भ, म; (approximants) य, र, ल, व; (fricatives) श, ष, स, ह.

I am archiving this information about the alphabet on the Hindi page: kirkkittell.com/language/hindi. More information from Wikipedia:

• Approximant consonants
• Sounds represented within /.../, e.g., /k/, are symbols of the International Phonetic Alphabet (IPA), which is extremely useful for me to understand how Hindi sounds.
• Sounds such as ka are transliterations from the International Alphabet of Sanskrit Transliteration (IAST). It's simpler to understand than IPA.

The fifth consonants -- प, फ, ब, भ, म -- are labial consonants ( Labial consonants). Labial consonants are articulated with the lips. Labial consonants are easy to say because they are analogous with sounds in the English language. This group of five consonants corresponds with p, b, and m in English. The trick is saying प and फ, ब and भ, with the proper aspiration. Even if it is easy for me to create the sounds, I have to concentrate on not aspirating प and ब because my innate tendency is to aspirate everything.

प
pa, /p/

फ
pha, /p^h/

प is said with no aspiration, फ is said with aspiration.

ब
ba, /b/

भ
bha, /b^h/

ब is said with no aspiration, भ is said with aspiration.

म
ma, /m/

म is a nasal consonant that sounds like the m in milk.

I am archiving this information about the alphabet on the Hindi page: kirkkittell.com/language/hindi. More information from Wikipedia:

• Labial consonants
• Sounds represented within /.../, e.g., /k/, are symbols of the International Phonetic Alphabet (IPA), which is extremely useful for me to understand how Hindi sounds.
• Sounds such as ka are transliterations from the International Alphabet of Sanskrit Transliteration (IAST). It's simpler to understand than IPA.

The fourth five consonants -- त, थ, द, ध, न -- are dental consonants ( Dental consonants). Just like it sounds, the dental consonants are related to your teeth. Dental consonants represent half of the strange d's and t's, cerebral consonants are the other half. Of course, by strange, I mean strange to me. The dental consonants are articulated by placing the tip of your tongue against the back of your teeth, whereas the cerebral consonants are made with the tip of the tongue against the roof of your mouth. Comparing the dental unaspirated ta, त, with the cerebral unaspirated ṭa, ट, is that ट sounds deeper and rounder than त.

त
ta, /t̪/

थ
tha, /t̪^h/

त is said with no aspiration, थ is said with aspiration.

द
da, /d̪/

ध
dha, /d̪^h/

द is said with no aspiration, ध is said with aspiration.

न
na, /n/

न is the most common nasal consonant.

I am archiving this information about the alphabet on the Hindi page: kirkkittell.com/language/hindi. More information from Wikipedia:

• Dental consonants
• Sounds represented within /.../, e.g., /k/, are symbols of the International Phonetic Alphabet (IPA), which is extremely useful for me to understand how Hindi sounds.
• Sounds such as ka are transliterations from the International Alphabet of Sanskrit Transliteration (IAST). It's simpler to understand than IPA.

The third five consonants -- ट, ठ, ड, ढ, ण -- are cerebral consonants ( Cerebral consonants). Apparently, in most phonetic systems, these are known as retroflex consonants, but in this and other languages in the region they are called cerebral consonants. From my point of view, as an American, cerebral consonants require tongue placement similar to the palatal consonants. In palatal consonants, such as /j/, the flat part fo the tongue presses against the hard palate on the roof of your mouth. In cerebral consonants, from this position in articulating a palatal consonant, the tip of the tongue touches the roof of the mouth behind the point where palatal consonants are articulated. (I may be wrong -- comments are welcome.)

The cerebral and dental d's and t's take some getting used to. I grew up with one d and one t in written English and no distinction between any of the different d's and t's in spoken English. But, in Hindi, there are four each: unaspirated cerebral; aspirated cerebral; unaspirated dental; aspirated dental.

ट
ṭa, /ʈ/

ठ
ṭha, /ʈ^h/

ट is said with no aspiration, ठ is said with aspiration.

ड
ḍa, /ɖ/

ढ
ḍha, /ɖ^h/

ड is said with no aspiration, ढ is said with aspiration.

ण
ṇa, /ɳ/

ण is the first common nasal consonant, i.e., you'll tend to see this one more than the previous two (ङ and ञ).

I am archiving this information about the alphabet on the Hindi page: kirkkittell.com/language/hindi. More information from Wikipedia:

• Cerebral consonants
• Sounds represented within /.../, e.g., /k/, are symbols of the International Phonetic Alphabet (IPA), which is extremely useful for me to understand how Hindi sounds.
• Sounds such as ka are transliterations from the International Alphabet of Sanskrit Transliteration (IAST). It's simpler to understand than IPA.

The second five consonants -- च, छ, ज, झ, ञ -- are palatal consonants ( Palatal consonants). Palatal consonants are articulated with the top, flat part of your tongue against the hard palate -- the middle of the roof of your mouth. This is easier to understand if you slowly say the j in jump or the ch in change. When you start to form the j or ch, feel where the contact is between your tongue and palate. (It is useful to understand where the palatal consonants are articulated to better understand where the cerebral consonants are articulated. j and ch are common sounds for an American, but the Hindi cerebral consonants are not. Cerebral consonants are formed by curling the tip of your tongue backwards against the roof of your mouth, just behind where the top of your tongue was for a palatal consonant.)

च ca, /c, ʧ/

छ cha, /c^h, ʧ^h/

च is said with no aspiration, i.e., with no puff of breath when you say it. छ is the same, except said with aspiration. Think of the transliteration of च, which is just a c, as more equivalent to the English ch, i.e., not as in ceiling or cat. However, since I tend to aspirate ch, the ch in chair sounds more like छ.

ज ja, /ɟ,ʤ/

झ jha, /ɟ^h, ʤ^h/

ज is said with no aspiration, झ is said with aspiration. ज is like the j in judge.

ञ ña, /ɲ/

ञ is a nasal consonant. You'll never see it at the start of a word. You'll never see it on its own. It seems to appear only rarely in text.

I am archiving this information about the alphabet on the Hindi page: kirkkittell.com/language/hindi. More information from Wikipedia:

• Palatal consonants
• Sounds represented within /.../, e.g., /k/, are symbols of the International Phonetic Alphabet (IPA), which is extremely useful for me to understand how Hindi sounds.
• Sounds such as ka are transliterations from the International Alphabet of Sanskrit Transliteration (IAST). It's simpler to understand than IPA.

When starting from the beginning in my Hindi studies, I learned an interesting concept about the arrangement of the Hindi alphabet: there is a reason the letters are in such an order. It is based on articulation of the consonants. I'm no linguist, but my understanding is that the consonants go in groups in this order: guttural; palatal; cerebral; dental; labial; approximant; fricative. Basically, but not entirely, this goes from the back of the throat (guttural) to the lips (labial). I'll lay it out in steps.

The first five consonants -- क, ख, ग, घ, ङ -- are guttural consonants ( Guttural). Guttural consonants are articulated in the throat. The first four are easy to say for a Midwestern American -- most of them, of at least.

क
ka, /k/

ख
kha, /k^h/

क is said with no aspiration, i.e., with no puff of breath when you say it. That requires practice for me. When I say words like kite, I aspirate the k. ख is said with aspiration.

ग
ga, /g/

घ
gha, /g^h/

Again, ग is said with no aspiration, घ is said with aspiration.

ङ
ṅa, /ŋ/

ङ is a nasal consonant. You'll never see it at the start of a word. You'll never see it on its own. You'll rarely see it in text.

I am archiving this information about the alphabet on the Hindi page: kirkkittell.com/language/hindi. More information from Wikipedia:

• Guttural consonants
• Sounds represented within /.../, e.g., /k/, are symbols of the International Phonetic Alphabet (IPA), which is extremely useful for me to understand how Hindi sounds.
• Sounds such as ka are transliterations from the International Alphabet of Sanskrit Transliteration (IAST) (IAST). It's simpler to understand than IPA.